diff --git a/.forgejo/workflows/deploy.yml b/.forgejo/workflows/deploy.yml
index 3555aa2..7008872 100644
--- a/.forgejo/workflows/deploy.yml
+++ b/.forgejo/workflows/deploy.yml
@@ -15,4 +15,4 @@ jobs:
           cache: true
       - run: git config --global --add safe.directory /opt/hostedtoolcache/flutter/stable-3.35.1-x64
       - run: flutter build web --release --wasm --base-href /app/
-      - run: sshpass -p "${{ secrets.DEPLOY_PASSWORD }}" scp -o StrictHostKeyChecking=accept-new -rp build/web ${{ secrets.DEPLOY_USERNAME }}@${{ secrets.DEPLOY_ADDRESS }}:${{ secrets.DEPLOY_PATH }}
+      - run: sshpass -p "${{ secrets.DEPLOY_PASSWORD }}" scp -o StrictHostKeyChecking=accept-new -rp build/web/* ${{ secrets.DEPLOY_USERNAME }}@${{ secrets.DEPLOY_ADDRESS }}:${{ secrets.DEPLOY_PATH }}
diff --git a/README.md b/README.md
index 304117b..a5a46b7 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,6 @@
+> [!WARNING]
+> This repo has been moved to [illes](https://git.illes.fr/UEAuvergne/Seshat).
+
 # seshat
 
 Client android/iOS/web, écrit en dart x flutter, pour Alexandria.
diff --git a/lib/data/repositories/auth_repository.dart b/lib/data/repositories/auth_repository.dart
index 2b56ddb..c55d564 100644
--- a/lib/data/repositories/auth_repository.dart
+++ b/lib/data/repositories/auth_repository.dart
@@ -2,6 +2,7 @@ import 'package:flutter/foundation.dart';
 import 'package:seshat/data/services/auth_client.dart';
 import 'package:seshat/utils/result.dart';
 
+/// Repository to manage authentification
 class AuthRepository extends ChangeNotifier {
   AuthRepository({required AuthClient authClient}) : _authClient = authClient;
 
@@ -9,6 +10,7 @@ class AuthRepository extends ChangeNotifier {
 
   bool? _isAuthenticated;
 
+  /// Checks the validity of the token if not already checked
   Future<bool> get isLoggedIn async {
     if (_isAuthenticated != null) {
       return _isAuthenticated!;
@@ -25,6 +27,7 @@ class AuthRepository extends ChangeNotifier {
     }
   }
 
+  /// Logs in the user
   Future<Result<void>> login(String username, String password) async {
     try {
       final result = await _authClient.login(username, password);
@@ -33,13 +36,14 @@ class AuthRepository extends ChangeNotifier {
           _isAuthenticated = true;
           return Result.ok(());
         case Error():
-          return Result.error(result.error);
+          return result;
       }
     } catch (e) {
       return Result.error(Exception(e));
     }
   }
 
+  /// Gets the API's remote version
   Future<Result<int>> getRemoteApiVersion() async {
     return await _authClient.getRemoteApiVersion();
   }
diff --git a/lib/data/repositories/bal_repository.dart b/lib/data/repositories/bal_repository.dart
index ccce2e4..97bc023 100644
--- a/lib/data/repositories/bal_repository.dart
+++ b/lib/data/repositories/bal_repository.dart
@@ -5,13 +5,19 @@ import 'package:seshat/domain/models/bal_stats.dart';
 import 'package:seshat/domain/models/enums.dart';
 import 'package:seshat/utils/result.dart';
 
+/// Repository to manage [Bal]
 class BalRepository {
   BalRepository({required ApiClient apiClient}) : _apiClient = apiClient;
 
   final ApiClient _apiClient;
-  List<Bal>? _bals;
-  Accounting? accounting;
 
+  /// [List<Bal>] of all the user's [Bal]
+  List<Bal>? _bals;
+
+  /// [Accounting] of [Bal], mapped by [Bal] id
+  final Map<int, Accounting?> _accountingMap = {};
+
+  /// Gets a list of all [Bal] from cache or remote
   Future<Result<List<Bal>>> getBals() async {
     if (_bals != null) {
       return Result.ok(_bals!);
@@ -26,6 +32,7 @@ class BalRepository {
     }
   }
 
+  /// Gets a list of all [Bal] from remote only
   Future<Result<List<Bal>>> _getBalsNoCache() async {
     final result = await _apiClient.getBals();
     switch (result) {
@@ -37,15 +44,16 @@ class BalRepository {
     }
   }
 
-  Future<Result<Bal>> balById(int id) async {
+  /// Gets a [Bal] by [balId], either from cache or remote
+  Future<Result<Bal>> balById(int balId) async {
     if (_bals == null) {
       await getBals();
     }
-    Bal? bal = _bals!.where((bal) => bal.id == id).firstOrNull;
+    Bal? bal = _bals!.where((bal) => bal.id == balId).firstOrNull;
     if (bal != null) {
       return Result.ok(bal);
     }
-    final result = await _apiClient.getBalById(id);
+    final result = await _apiClient.getBalById(balId);
     switch (result) {
       case Ok():
         return Result.ok(result.value);
@@ -54,11 +62,13 @@ class BalRepository {
     }
   }
 
+  /// Return wether or not a [Bal] is currently [BalState.ongoing]
   bool isABalOngoing() {
     return _bals?.where((bal) => bal.state == BalState.ongoing).isNotEmpty ??
         false;
   }
 
+  /// Gets the [Bal] that is [BalState.ongoing]
   Future<Bal?> ongoingBal() async {
     if (_bals == null) {
       await _getBalsNoCache();
@@ -66,12 +76,14 @@ class BalRepository {
     return _bals!.where((bal) => bal.state == BalState.ongoing).firstOrNull;
   }
 
+  /// Stops a [Bal] and refresh cache
   Future<Result<Bal>> stopBal(int id) async {
     final result = await _apiClient.stopBal(id);
     _getBalsNoCache();
     return result;
   }
 
+  /// Starts a [Bal] and refresh cache
   Future<Result<Bal>> startBal(int id) async {
     if (isABalOngoing()) {
       return Result.error(
@@ -83,52 +95,62 @@ class BalRepository {
     return result;
   }
 
+  /// Changes a [Bal]'s [name], [startTime] or [endTime]
   Future<Result<Bal>> editBal(
     int id,
     String name,
-    DateTime start,
-    DateTime end,
+    DateTime startTime,
+    DateTime endTime,
   ) async {
-    final result = await _apiClient.editBal(id, name, start, end);
+    final result = await _apiClient.editBal(id, name, startTime, endTime);
     await _getBalsNoCache();
     return result;
   }
 
-  Future<Result<void>> addBal(String name, DateTime start, DateTime end) async {
-    final result = await _apiClient.addBal(name, start, end);
+  /// Creates a [Bal] from its [name], [startTime] and [endTime]
+  Future<Result<void>> addBal(
+    String name,
+    DateTime startTime,
+    DateTime endTime,
+  ) async {
+    final result = await _apiClient.addBal(name, startTime, endTime);
     await _getBalsNoCache();
     return result;
   }
 
-  Future<Result<BalStats>> getBalStats(int id) async {
-    return _apiClient.getBalStats(id);
+  /// Gets a [BalStats] from its [balId]
+  Future<Result<BalStats>> getBalStats(int balId) async {
+    return _apiClient.getBalStats(balId);
   }
 
+  /// Get [Accounting] of a [Bal] from remote only
   Future<Result<Accounting>> getAccountingNoCache(int balId) async {
     final result = await _apiClient.getAccounting(balId);
     switch (result) {
       case Ok():
-        accounting = result.value;
+        _accountingMap[balId] = result.value;
         break;
       default:
     }
     return result;
   }
 
+  /// Get [Accounting] of a [Bal] from cache or remote
   Future<Result<Accounting>> getAccounting(int balId) async {
-    if (accounting != null) {
-      return Result.ok(accounting!);
+    if (_accountingMap[balId] != null) {
+      return Result.ok(_accountingMap[balId]!);
     }
     final result = await _apiClient.getAccounting(balId);
     switch (result) {
       case Ok():
-        accounting = result.value;
+        _accountingMap[balId] = result.value;
         break;
       default:
     }
     return result;
   }
 
+  /// Manages what returning (of type [ReturnType]) does to cache and notifies remote
   Future<Result<void>> returnToId(
     int balId,
     int ownerId,
@@ -139,26 +161,32 @@ class BalRepository {
       case Ok():
         switch (type) {
           case ReturnType.books:
-            final owner = accounting?.owners
+            final owner = _accountingMap[balId]?.owners
                 .where((el) => el.ownerId == ownerId)
                 .firstOrNull;
             if (owner?.owedMoney == 0) {
-              accounting?.owners.removeWhere((el) => el.ownerId == ownerId);
+              _accountingMap[balId]?.owners.removeWhere(
+                (el) => el.ownerId == ownerId,
+              );
             }
             owner?.owed = [];
             owner?.owedInstances = [];
             break;
           case ReturnType.money:
-            final owner = accounting?.owners
+            final owner = _accountingMap[balId]?.owners
                 .where((el) => el.ownerId == ownerId)
                 .firstOrNull;
             if (owner?.owed == null || owner!.owed.isEmpty) {
-              accounting?.owners.removeWhere((el) => el.ownerId == ownerId);
+              _accountingMap[balId]?.owners.removeWhere(
+                (el) => el.ownerId == ownerId,
+              );
             }
             owner?.owedMoney = 0;
             break;
           case ReturnType.all:
-            accounting?.owners.removeWhere((el) => el.ownerId == ownerId);
+            _accountingMap[balId]?.owners.removeWhere(
+              (el) => el.ownerId == ownerId,
+            );
             break;
         }
         break;
diff --git a/lib/data/repositories/book_instance_repository.dart b/lib/data/repositories/book_instance_repository.dart
index 4a07167..7a60d19 100644
--- a/lib/data/repositories/book_instance_repository.dart
+++ b/lib/data/repositories/book_instance_repository.dart
@@ -6,16 +6,19 @@ import 'package:seshat/domain/models/owner.dart';
 import 'package:seshat/domain/models/search_result.dart';
 import 'package:seshat/utils/result.dart';
 
+/// Repository to manage [BookInstance]
 class BookInstanceRepository {
   BookInstanceRepository({required ApiClient apiClient})
     : _apiClient = apiClient;
 
   final ApiClient _apiClient;
 
+  /// Gets a [List<BookInstance>] from an [ean]
   Future<Result<List<BookInstance>>> getByEan(int balId, int ean) async {
     return await _apiClient.getBookInstanceByEAN(balId, ean);
   }
 
+  /// Gets a [List<BookInstance>] from a [title] and [author]
   Future<Result<List<SearchResult>>> getBySearch(
     int balId,
     String title,
@@ -24,15 +27,17 @@ class BookInstanceRepository {
     return await _apiClient.getBookInstanceBySearch(balId, title, author);
   }
 
-  Future<Result<BookInstance>> sendBook(
+  /// Sends a new [BookInstance]'s [book], [owner], [bal] and [price]
+  Future<Result<BookInstance>> sendNewBookInstance(
     Book book,
     Owner owner,
     Bal bal,
     double price,
   ) async {
-    return await _apiClient.sendBook(book, owner, bal, price);
+    return await _apiClient.sendNewBookInstance(book, owner, bal, price);
   }
 
+  /// Sells a [List<BookInstance>]
   Future<Result<void>> sellBooks(List<BookInstance> books) async {
     Map<String, double?> res = {};
     for (BookInstance instance in books) {
diff --git a/lib/data/repositories/book_repository.dart b/lib/data/repositories/book_repository.dart
index 984d85b..5d38be1 100644
--- a/lib/data/repositories/book_repository.dart
+++ b/lib/data/repositories/book_repository.dart
@@ -2,16 +2,19 @@ import 'package:seshat/data/services/api_client.dart';
 import 'package:seshat/domain/models/book.dart';
 import 'package:seshat/utils/result.dart';
 
+/// Repository to manage [Book]
 class BookRepository {
   BookRepository({required ApiClient apiClient}) : _apiClient = apiClient;
 
   final ApiClient _apiClient;
 
+  /// Gets a [Book] by its [ean]
   Future<Result<Book>> getBookByEAN(String ean) async {
     return await _apiClient.getBookByEAN(ean);
   }
 
-  Future<Result<Book>> getBookById(int id) async {
-    return await _apiClient.getBookById(id);
+  /// Gets a [Book] by its [bookId]
+  Future<Result<Book>> getBookById(int bookId) async {
+    return await _apiClient.getBookById(bookId);
   }
 }
diff --git a/lib/data/repositories/owner_repository.dart b/lib/data/repositories/owner_repository.dart
index 5020123..817bea0 100644
--- a/lib/data/repositories/owner_repository.dart
+++ b/lib/data/repositories/owner_repository.dart
@@ -5,6 +5,7 @@ import 'package:seshat/data/services/websocket_client.dart';
 import 'package:seshat/domain/models/owner.dart';
 import 'package:seshat/utils/result.dart';
 
+/// Repository to manage [Owner]
 class OwnerRepository {
   OwnerRepository({
     required ApiClient apiClient,
@@ -14,18 +15,25 @@ class OwnerRepository {
 
   final ApiClient _apiClient;
   final WebsocketClient _wsClient;
-  late final StreamSubscription sub;
-  List<Owner>? _cachedOwners;
-  Owner? _sectionOwner;
 
-  Future<Result<Owner>> get sectionOwner async {
-    if (_sectionOwner != null) {
-      return Result.ok(_sectionOwner!);
+  /// [StreamSubscription] to the [Stream<Owner>] for [_wsClient]
+  late final StreamSubscription sub;
+
+  /// [List<Owner>] of owners, updated by [_wsClient]
+  List<Owner>? _cachedOwners;
+
+  /// [Owner] of the current user
+  Owner? _ownerOfUser;
+
+  /// [Owner] of the current user
+  Future<Result<Owner>> get ownerOfUser async {
+    if (_ownerOfUser != null) {
+      return Result.ok(_ownerOfUser!);
     }
-    final result = await _apiClient.getSectionOwner();
+    final result = await _apiClient.getOwnerOfUser();
     switch (result) {
       case Ok():
-        _sectionOwner = result.value;
+        _ownerOfUser = result.value;
         break;
       default:
         break;
@@ -33,16 +41,17 @@ class OwnerRepository {
     return result;
   }
 
-  Future<Result<Owner>> getOwnerById(int id) async {
+  /// Gets an [Owner] from its [ownerId]
+  Future<Result<Owner>> getOwnerById(int ownerId) async {
     if (_cachedOwners != null) {
       final result1 = _cachedOwners!
-          .where((owner) => owner.id == id)
+          .where((owner) => owner.id == ownerId)
           .firstOrNull;
       if (result1 != null) {
         return Result.ok(result1);
       }
     }
-    return await _apiClient.getOwnerById(id);
+    return await _apiClient.getOwnerById(ownerId);
   }
 
   /// Adds an [Owner] to the database, and gets the resulting [Owner].
diff --git a/lib/data/services/api_client.dart b/lib/data/services/api_client.dart
index 2d9e273..c638d4c 100644
--- a/lib/data/services/api_client.dart
+++ b/lib/data/services/api_client.dart
@@ -1,7 +1,5 @@
 import 'dart:convert';
 
-import 'package:flutter/rendering.dart';
-import 'package:flutter/widgets.dart';
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 import 'package:http/http.dart';
 import 'package:logger/logger.dart';
@@ -11,9 +9,9 @@ import 'package:seshat/domain/models/bal.dart';
 import 'package:seshat/domain/models/bal_stats.dart';
 import 'package:seshat/domain/models/book.dart';
 import 'package:seshat/domain/models/book_instance.dart';
+import 'package:seshat/domain/models/enums.dart';
 import 'package:seshat/domain/models/owner.dart';
 import 'package:seshat/domain/models/search_result.dart';
-import 'package:seshat/utils/command.dart';
 import 'package:seshat/utils/result.dart';
 
 extension StringExtension on String {
@@ -22,12 +20,17 @@ extension StringExtension on String {
   }
 }
 
+/// API Client to manage all authenticated REST routes
 class ApiClient {
-  ApiClient({String? host, int? port});
+  ApiClient();
 
-  late final Command0 load;
+  /// JWT for registration
   String? token;
+
+  /// Readiness of the API Client
   bool isReady = false;
+
+  /// Storage to access JWT
   FlutterSecureStorage? _secureStorage;
   Logger log = Logger(
     printer: PrettyPrinter(
@@ -38,10 +41,12 @@ class ApiClient {
     ),
   );
 
+  /// Initializes connection to the [_secureStorage]
   Future<void> _initStore() async {
-    _secureStorage ??= const FlutterSecureStorage(aOptions: AndroidOptions());
+    _secureStorage ??= const FlutterSecureStorage();
   }
 
+  /// Generates authorization headers and option [additionalHeaders]
   Future<Map<String, String>> _getHeaders([
     Map<String, String>? additionalHeaders,
   ]) async {
@@ -57,6 +62,7 @@ class ApiClient {
  * ========================
 */
 
+  /// Gets data about a BAL's needed returns
   Future<Result<Accounting>> getAccounting(int balId) async {
     final url = "https://$apiBasePath/bal/$balId/accounting";
     log.i("Fetching: getAccounting ($url)");
@@ -83,6 +89,8 @@ class ApiClient {
     }
   }
 
+  /// Notifies the server that either Books, Money or All has been returned to the user
+  /// [type] is the stringified version of [ReturnType]
   Future<Result<void>> returnToId(int balId, int ownerId, String type) async {
     final url =
         "https://$apiBasePath/bal/${balId.toString()}/accounting/return/${ownerId.toString()}";
@@ -122,8 +130,9 @@ class ApiClient {
  * =================
 */
 
-  Future<Result<BalStats>> getBalStats(int id) async {
-    final url = "https://$apiBasePath/bal/${id.toString()}/stats";
+  /// Get stats about a BAL's performance
+  Future<Result<BalStats>> getBalStats(int balId) async {
+    final url = "https://$apiBasePath/bal/${balId.toString()}/stats";
     log.i("Fetching: getBalStats ($url)");
     final client = Client();
     try {
@@ -150,8 +159,9 @@ class ApiClient {
     }
   }
 
-  Future<Result<Bal>> stopBal(int id) async {
-    final url = "https://$apiBasePath/bal/${id.toString()}/stop";
+  /// Stops a BAL, putting it's [BalState] to [BalState.ended]
+  Future<Result<Bal>> stopBal(int balId) async {
+    final url = "https://$apiBasePath/bal/${balId.toString()}/stop";
     log.i("Fetching: stopBal ($url)");
     final client = Client();
     try {
@@ -178,8 +188,9 @@ class ApiClient {
     }
   }
 
-  Future<Result<Bal>> startBal(int id) async {
-    final url = "https://$apiBasePath/bal/${id.toString()}/start";
+  /// Starts a BAL, putting it's [BalState] to [BalState.ongoing]
+  Future<Result<Bal>> startBal(int balId) async {
+    final url = "https://$apiBasePath/bal/${balId.toString()}/start";
     log.i("Fetching: startBal ($url)");
     final client = Client();
     try {
@@ -206,21 +217,22 @@ class ApiClient {
     }
   }
 
+  /// Changes the information about a [Bal], such as its [name], [startTime] or [endTime]
   Future<Result<Bal>> editBal(
-    int id,
+    int balId,
     String name,
-    DateTime start,
-    DateTime end,
+    DateTime startTime,
+    DateTime endTime,
   ) async {
-    final url = "https://$apiBasePath/bal/${id.toString()}";
+    final url = "https://$apiBasePath/bal/${balId.toString()}";
     log.i("Fetching: editBal ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders({"Content-Type": "application/json"});
       final body = {
         "name": name,
-        "start_timestamp": (start.millisecondsSinceEpoch / 1000).round(),
-        "end_timestamp": (end.millisecondsSinceEpoch / 1000).round(),
+        "start_timestamp": (startTime.millisecondsSinceEpoch / 1000).round(),
+        "end_timestamp": (endTime.millisecondsSinceEpoch / 1000).round(),
       };
       final response = await client.patch(
         Uri.parse(url),
@@ -246,8 +258,9 @@ class ApiClient {
     }
   }
 
-  Future<Result<Bal>> getBalById(int id) async {
-    final url = "https://$apiBasePath/bal/${id.toString()}";
+  /// Gets a [Bal] from it's [balId]
+  Future<Result<Bal>> getBalById(int balId) async {
+    final url = "https://$apiBasePath/bal/${balId.toString()}";
     log.i("Fetching: getBalById ($url)");
     final client = Client();
     try {
@@ -272,7 +285,12 @@ class ApiClient {
     }
   }
 
-  Future<Result<Bal>> addBal(String name, DateTime start, DateTime end) async {
+  /// Adds a [Bal] from it's [name], [startTime] and [endTime]
+  Future<Result<Bal>> addBal(
+    String name,
+    DateTime startTime,
+    DateTime endTime,
+  ) async {
     final url = "https://$apiBasePath/bal";
     log.i("Fetching: addBal ($url)");
     final client = Client();
@@ -280,8 +298,8 @@ class ApiClient {
       final headers = await _getHeaders({"Content-Type": "application/json"});
       final body = {
         "name": name,
-        "start_timestamp": (start.millisecondsSinceEpoch / 1000).round(),
-        "end_timestamp": (end.millisecondsSinceEpoch / 1000).round(),
+        "start_timestamp": (startTime.millisecondsSinceEpoch / 1000).round(),
+        "end_timestamp": (endTime.millisecondsSinceEpoch / 1000).round(),
       };
       final response = await client.post(
         Uri.parse(url),
@@ -305,6 +323,7 @@ class ApiClient {
     }
   }
 
+  /// Gets a [List<Bal>] of all [Bal]
   Future<Result<List<Bal>>> getBals() async {
     final url = "https://$apiBasePath/bals";
     log.i("Fetching: getBals ($url)");
@@ -312,28 +331,32 @@ class ApiClient {
     try {
       final headers = await _getHeaders();
       final response = await client.get(Uri.parse(url), headers: headers);
-      if (response.statusCode == 200) {
-        final json = jsonDecode(response.body) as List<dynamic>;
-        return Result.ok(json.map((element) => Bal.fromJSON(element)).toList());
-      } else {
-        throw Exception("Something wrong happened");
+
+      switch (response.statusCode) {
+        case 200:
+          final json = jsonDecode(response.body) as List<dynamic>;
+          return Result.ok(
+            json.map((element) => Bal.fromJSON(element)).toList(),
+          );
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
     } catch (e) {
-      debugPrint("ERROR: ${e.toString()}");
+      log.e(e.toString());
       return Result.error(Exception(e));
     } finally {
       client.close();
     }
   }
 
-  Future<Result<Bal?>> getCurrentBal() async {
+  /// Gets the ongoing BAL for the user
+  Future<Result<Bal?>> getOngoingBal() async {
+    final url = "https://$apiBasePath/bal/current";
+    log.i("Fetching: getCurrentBal ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders();
-      final response = await client.get(
-        Uri.parse("https://$apiBasePath/bal/current"),
-        headers: headers,
-      );
+      final response = await client.get(Uri.parse(url), headers: headers);
       if (response.statusCode == 200) {
         final json = jsonDecode(response.body);
         return Result.ok(Bal.fromJSON(json));
@@ -355,42 +378,50 @@ class ApiClient {
  * ===================
 */
 
-  Future<Result<Book>> getBookById(int id) async {
+  /// Gets a [Book] by its [bookId]
+  Future<Result<Book>> getBookById(int bookId) async {
+    final url = "https://$apiBasePath/book/id/${bookId.toString()}";
+    log.i("Fetching: getBookById ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders();
-      final response = await client.get(
-        Uri.parse("https://$apiBasePath/book/id/${id.toString()}"),
-        headers: headers,
-      );
-      if (response.statusCode == 200) {
-        final json = jsonDecode(response.body);
-        return Result.ok(Book.fromJSON(json));
-      } else {
-        throw Exception("The book was not found");
+      final response = await client.get(Uri.parse(url), headers: headers);
+      switch (response.statusCode) {
+        case 200:
+          final json = jsonDecode(response.body);
+          return Result.ok(Book.fromJSON(json));
+        case 404:
+          throw "No book with this id exists in database";
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
     } catch (e) {
+      log.e(e.toString());
       return Result.error(Exception("API $e"));
     } finally {
       client.close();
     }
   }
 
+  /// Gets a [Book] from its [ean]
   Future<Result<Book>> getBookByEAN(String ean) async {
+    final url = "https://$apiBasePath/book/ean/$ean";
+    log.i("Fetching: getBookByEan ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders();
-      final response = await client.get(
-        Uri.parse("https://$apiBasePath/book/ean/$ean"),
-        headers: headers,
-      );
-      if (response.statusCode == 200) {
-        final json = jsonDecode(response.body);
-        return Result.ok(Book.fromJSON(json));
-      } else {
-        throw Exception("The book was not found");
+      final response = await client.get(Uri.parse(url), headers: headers);
+      switch (response.statusCode) {
+        case 200:
+          final json = jsonDecode(response.body);
+          return Result.ok(Book.fromJSON(json));
+        case 404:
+          throw "No book with this EAN found in the database of BNF";
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
     } catch (e) {
+      log.e(e.toString());
       return Result.error(Exception("API $e"));
     } finally {
       client.close();
@@ -403,93 +434,118 @@ class ApiClient {
  * =============================
 */
 
+  /// Gets a [BookInstance] from it's [title], [author] or both
   Future<Result<List<SearchResult>>> getBookInstanceBySearch(
     int balId,
     String title,
     String author,
   ) async {
+    final url = "https://$apiBasePath/bal/${balId.toString()}/search";
+    log.i("Fetching: getBookInstancesBySearch ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders({"Content-Type": "application/json"});
       final body = jsonEncode({"title": title, "author": author});
-      debugPrint("\n\n\n\n$body\n\n\n\n");
       final response = await client.post(
-        Uri.parse("https://$apiBasePath/bal/${balId.toString()}/search"),
+        Uri.parse(url),
         headers: headers,
         body: body,
       );
-      if (response.statusCode == 200) {
-        final json = jsonDecode(response.body) as List<dynamic>;
-        debugPrint("\n\n\n\nJSON : $json\n\n\n\n");
-        return Result.ok(json.map((el) => SearchResult.fromJSON(el)).toList());
-      } else {
-        throw "Unknown Error";
+      switch (response.statusCode) {
+        case 200:
+          final json = jsonDecode(response.body) as List<dynamic>;
+          return Result.ok(
+            json.map((el) => SearchResult.fromJSON(el)).toList(),
+          );
+        case 403:
+          throw "You do not own the BAL";
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
     } catch (e) {
-      debugPrint("\n\n\n\nERROR: ${e.toString()}\n\n\n\n");
+      log.e(e.toString());
       return Result.error(Exception("API $e"));
     } finally {
       client.close();
     }
   }
 
+  /// Gets a [BookInstance] from it's [ean]
   Future<Result<List<BookInstance>>> getBookInstanceByEAN(
     int balId,
     int ean,
   ) async {
+    final url =
+        "https://$apiBasePath/bal/${balId.toString()}/ean/${ean.toString()}/book_instances";
+    log.i("Fetching: getBookInstancesByEan ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders();
-      final response = await client.get(
-        Uri.parse(
-          "https://$apiBasePath/bal/${balId.toString()}/ean/${ean.toString()}/book_instances",
-        ),
-        headers: headers,
-      );
-      if (response.statusCode == 200) {
-        final json = jsonDecode(response.body) as List<dynamic>;
-        return Result.ok(json.map((el) => BookInstance.fromJSON(el)).toList());
-      } else {
-        throw "Unknown Error";
+      final response = await client.get(Uri.parse(url), headers: headers);
+      switch (response.statusCode) {
+        case 200:
+          final json = jsonDecode(response.body) as List<dynamic>;
+          return Result.ok(
+            json.map((el) => BookInstance.fromJSON(el)).toList(),
+          );
+        case 403:
+          throw "You do not own the BAL";
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
     } catch (e) {
+      log.e(e.toString());
       return Result.error(Exception("API $e"));
     } finally {
       client.close();
     }
   }
 
+  /// Notifies the server of the sell of multiple [BookInstance]. [books] is in the form of
+  /// ```dart
+  /// final books = {"aBookInstanceId": 6.0} // and its price
+  /// ```
   Future<Result<void>> sellBooks(Map<String, double?> books) async {
+    final url = "https://$apiBasePath/book_instance/sell/bulk";
+    log.i("Fetching: sellBooks ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders({"Content-Type": "application/json"});
-      debugPrint("\n\n\n\nMAP: $books\n\n\n\n");
       final body = jsonEncode(books);
-      debugPrint("\n\n\n\nSENT: $body\n\n\n\n");
       final response = await client.post(
-        Uri.parse("https://$apiBasePath/book_instance/sell/bulk"),
+        Uri.parse(url),
         headers: headers,
         body: body,
       );
-      if (response.statusCode == 200) {
-        return Result.ok(response.statusCode);
-      } else {
-        throw "Unknown error";
+      switch (response.statusCode) {
+        case 200:
+          return Result.ok(response.statusCode);
+        case 403:
+          throw "You don't own one of the specified books";
+        case 404:
+          throw "One of the books was not found";
+        case 409:
+          throw "One of the books wasn't available";
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
     } catch (e) {
-      debugPrint("\n\n\n\nERROR : ${e.toString()}\n\n\n\n");
+      log.e(e.toString());
       return Result.error(Exception(e));
     } finally {
       client.close();
     }
   }
 
-  Future<Result<BookInstance>> sendBook(
+  /// Creates a new [BookInstance] from it's [book], it's [owner], it's [bal] and it's [price]
+  Future<Result<BookInstance>> sendNewBookInstance(
     Book book,
     Owner owner,
     Bal bal,
     double price,
   ) async {
+    final url = "https://$apiBasePath/book_instance";
+    log.i("Fetching: sendBook ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders({"Content-Type": "application/json"});
@@ -500,17 +556,18 @@ class ApiClient {
         "price": price,
       });
       final response = await client.post(
-        Uri.parse("https://$apiBasePath/book_instance"),
+        Uri.parse(url),
         headers: headers,
         body: body,
       );
-      if (response.statusCode == 201) {
-        final json = jsonDecode(response.body);
-        return Result.ok(BookInstance.fromJSON(json));
-      } else if (response.statusCode == 403) {
-        throw Exception("You don't own that book instance");
-      } else {
-        throw Exception("Something wrong happened");
+      switch (response.statusCode) {
+        case 201:
+          final json = jsonDecode(response.body);
+          return Result.ok(BookInstance.fromJSON(json));
+        case 403:
+          throw "You don't own that book instance";
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
     } catch (e) {
       return Result.error(Exception(e));
@@ -525,64 +582,72 @@ class ApiClient {
  * ====================
 */
 
-  Future<Result<Owner>> getOwnerById(int id) async {
+  /// Gets an [Owner] by it's [ownerId]
+  Future<Result<Owner>> getOwnerById(int ownerId) async {
+    final url = "https://$apiBasePath/owner/${ownerId.toString()}";
+    log.i("Fetching: getOwnerById ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders();
-      final response = await client.get(
-        Uri.parse("https://$apiBasePath/owner/${id.toString()}"),
-        headers: headers,
-      );
-      if (response.statusCode == 200) {
-        final json = jsonDecode(response.body);
-        return Result.ok(Owner.fromJSON(json));
-      } else {
-        throw Exception("The owner was not found");
+      final response = await client.get(Uri.parse(url), headers: headers);
+      switch (response.statusCode) {
+        case 200:
+          final json = jsonDecode(response.body);
+          return Result.ok(Owner.fromJSON(json));
+        case 403:
+          throw "You do not own specified owner";
+        case 404:
+          throw "No owner with this id exists";
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
     } catch (e) {
+      log.e(e.toString());
       return Result.error(Exception("API $e"));
     } finally {
       client.close();
     }
   }
 
-  Future<Result<Owner>> getSectionOwner() async {
+  /// Get the owner of the current user
+  Future<Result<Owner>> getOwnerOfUser() async {
+    final url = "https://$apiBasePath/owner/self";
+    log.i("Fetching: getSectionOwner ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders();
-      final response = await client.get(
-        Uri.parse("https://$apiBasePath/owner/self"),
-        headers: headers,
-      );
-      if (response.statusCode == 200) {
-        final json = jsonDecode(response.body);
-        return Result.ok(Owner.fromJSON(json));
-      } else {
-        throw "Unknown error";
+      final response = await client.get(Uri.parse(url), headers: headers);
+      switch (response.statusCode) {
+        case 200:
+          final json = jsonDecode(response.body);
+          return Result.ok(Owner.fromJSON(json));
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
     } catch (e) {
+      log.e(e.toString());
       return Result.error(Exception(e));
     } finally {
       client.close();
     }
   }
 
-  /// Call on `/owners` to get a list of all [Owner]s
+  /// Get a [List<Owner>] of all [Owner]
   Future<Result<List<Owner>>> getOwners() async {
+    final url = "https://$apiBasePath/owners";
+    log.i("Fetching: getOwners ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders();
-      final response = await client.get(
-        Uri.parse("https://$apiBasePath/owners"),
-        headers: headers,
-      );
-      if (response.statusCode == 200) {
-        final json = jsonDecode(response.body) as List<dynamic>;
-        return Result.ok(
-          json.map((element) => Owner.fromJSON(element)).toList(),
-        );
-      } else {
-        throw Exception("Invalid request");
+      final response = await client.get(Uri.parse(url), headers: headers);
+      switch (response.statusCode) {
+        case 200:
+          final json = jsonDecode(response.body) as List<dynamic>;
+          return Result.ok(
+            json.map((element) => Owner.fromJSON(element)).toList(),
+          );
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
     } on Exception catch (error) {
       return Result.error(error);
@@ -591,12 +656,14 @@ class ApiClient {
     }
   }
 
-  /// Adds an owner to the database
+  /// Adds an [Owner] from its [firstName], [lastName] and [contact]
   Future<Result<Owner>> addOwner(
     String firstName,
     String lastName,
     String contact,
   ) async {
+    final url = "https://$apiBasePath/owner";
+    log.i("Fetching: addOwner ($url)");
     final client = Client();
     try {
       final headers = await _getHeaders({"Content-Type": "application/json"});
@@ -606,18 +673,20 @@ class ApiClient {
         "contact": contact,
       };
       final response = await client.post(
-        Uri.parse("https://$apiBasePath/owner"),
+        Uri.parse(url),
         headers: headers,
         body: jsonEncode(body),
       );
-      if (response.statusCode == 201) {
-        final json = jsonDecode(response.body);
-        return Result.ok(Owner.fromJSON(json));
-      } else {
-        throw Exception("Invalid request");
+      switch (response.statusCode) {
+        case 201:
+          final json = jsonDecode(response.body);
+          return Result.ok(Owner.fromJSON(json));
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
-    } on Exception catch (error) {
-      return Result.error(error);
+    } catch (e) {
+      log.e(e.toString());
+      return Result.error(Exception(e));
     } finally {
       client.close();
     }
diff --git a/lib/data/services/auth_client.dart b/lib/data/services/auth_client.dart
index 4d77b4f..3dc8496 100644
--- a/lib/data/services/auth_client.dart
+++ b/lib/data/services/auth_client.dart
@@ -1,29 +1,43 @@
 import 'dart:convert';
 
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
+import 'package:logger/logger.dart';
 import 'package:seshat/config/constants.dart';
 import 'package:seshat/utils/result.dart';
-import "package:http/http.dart" as http;
+import "package:http/http.dart";
 
+/// API Client to manage all unauthenticated REST routes
 class AuthClient {
   AuthClient();
-  FlutterSecureStorage? _secureStorage;
 
+  /// Storage to access JWT
+  FlutterSecureStorage? _secureStorage;
+  Logger log = Logger(
+    printer: PrettyPrinter(
+      colors: true,
+      lineLength: 100,
+      methodCount: 0,
+      dateTimeFormat: DateTimeFormat.dateAndTime,
+    ),
+  );
+
+  /// Initializes connection to the [_secureStorage]
   Future<void> _initStore() async {
-    _secureStorage ??= const FlutterSecureStorage(
-      aOptions: AndroidOptions(encryptedSharedPreferences: true),
-    );
+    _secureStorage ??= const FlutterSecureStorage();
   }
 
+  /// Verifies the validity of the token stored in [_secureStorage]
   Future<Result<bool>> hasValidToken() async {
+    final url = "https://$apiBasePath/token-check";
+    log.i("Fetching: hasValidToken ($url)");
+    final client = Client();
     try {
       await _initStore();
       bool hasToken = await _secureStorage!.containsKey(key: "token");
       if (hasToken) {
         var token = await _secureStorage!.read(key: "token");
-        var url = Uri.parse("https://$apiBasePath/token-check");
-        var response = await http.post(
-          url,
+        var response = await client.post(
+          Uri.parse(url),
           headers: {"Content-Type": "application/json"},
           body: jsonEncode({"token": token}),
         );
@@ -34,52 +48,64 @@ class AuthClient {
       }
       return Result.ok(false);
     } catch (e) {
-      return Result.error(Exception(e));
-    }
-  }
-
-  Future<Result<String>> login(String username, String password) async {
-    var client = http.Client();
-    try {
-      await _initStore();
-      var url = Uri.parse("https://$apiBasePath/auth");
-      var response = await client.post(
-        url,
-        headers: {
-          "Content-Type": "application/json",
-          "Accept": "application/json",
-        },
-        body: jsonEncode({"password": password, "username": username}),
-      );
-      if (response.statusCode == 200) {
-        var json = jsonDecode(response.body);
-        await _secureStorage!.write(key: "token", value: json["access_token"]);
-        return Result.ok(json["access_token"]);
-      } else if (response.statusCode == 401) {
-        return Result.error(Exception("Wrong credentials"));
-      } else {
-        return Result.error(Exception("Token creation error"));
-      }
-    } catch (e) {
+      log.e(e.toString());
       return Result.error(Exception(e));
     } finally {
       client.close();
     }
   }
 
-  Future<Result<int>> getRemoteApiVersion() async {
-    final client = http.Client();
+  /// Logs a user in from its [username] and [password]
+  Future<Result<String>> login(String username, String password) async {
+    final url = "https://$apiBasePath/auth";
+    log.i("Logging in: $url");
+    var client = Client();
     try {
-      final response = await client.get(
-        Uri.parse("https://$apiBasePath/version"),
+      await _initStore();
+      var response = await client.post(
+        Uri.parse(url),
+        headers: {"Content-Type": "application/json"},
+        body: jsonEncode({"password": password, "username": username}),
       );
-      if (response.statusCode == 200) {
-        final json = jsonDecode(response.body) as int;
-        return Result.ok(json);
-      } else {
-        throw "Something wrong happened";
+      switch (response.statusCode) {
+        case 200:
+          var json = jsonDecode(response.body);
+          await _secureStorage!.write(
+            key: "token",
+            value: json["access_token"],
+          );
+          return Result.ok(json["access_token"]);
+        case 401:
+          throw "Wrong credentials";
+        case 500:
+          throw "Token creation error";
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
       }
     } catch (e) {
+      log.e(e.toString());
+      return Result.error(Exception(e));
+    } finally {
+      client.close();
+    }
+  }
+
+  /// Gets the API version of the server
+  Future<Result<int>> getRemoteApiVersion() async {
+    final url = "https://$apiBasePath/version";
+    log.i("Fetching: getRemoteApiVersion ($url)");
+    final client = Client();
+    try {
+      final response = await client.get(Uri.parse(url));
+      switch (response.statusCode) {
+        case 200:
+          final json = jsonDecode(response.body) as int;
+          return Result.ok(json);
+        default:
+          throw "Unknown error with code ${response.statusCode.toString()}";
+      }
+    } catch (e) {
+      log.e(e.toString());
       return Result.error(Exception(e));
     } finally {
       client.close();
diff --git a/lib/data/services/websocket_client.dart b/lib/data/services/websocket_client.dart
index f8df18a..1d85989 100644
--- a/lib/data/services/websocket_client.dart
+++ b/lib/data/services/websocket_client.dart
@@ -2,33 +2,55 @@ import 'dart:async';
 import 'dart:convert';
 
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
+import 'package:logger/logger.dart';
 import 'package:rxdart/rxdart.dart';
 import 'package:seshat/config/constants.dart';
 import 'package:seshat/domain/models/owner.dart';
 import 'package:web_socket_channel/web_socket_channel.dart';
 
+/// API Client to manages connections to WebSockets
 class WebsocketClient {
-  WebSocketChannel? _channel;
+  /// Storage to access JWT
   FlutterSecureStorage? _secureStorage;
+
+  /// Raw channel of data from WebSocket
+  WebSocketChannel? _channel;
+
+  /// Global WebSocket Stream
   final BehaviorSubject<dynamic> _baseController = BehaviorSubject();
+
+  /// WebSocket Stream dedicated to [Owner] entries
   final BehaviorSubject<Owner> _ownersController = BehaviorSubject<Owner>(
     sync: true,
   );
-  late final StreamSubscription sub;
 
+  /// Subscription to [_baseController]
+  late final StreamSubscription sub;
+  Logger log = Logger(
+    printer: PrettyPrinter(
+      colors: true,
+      lineLength: 100,
+      methodCount: 0,
+      dateTimeFormat: DateTimeFormat.dateAndTime,
+    ),
+  );
+
+  /// Gets a stream of [Owner]
   Stream<Owner> get owners => _ownersController.stream;
 
+  /// Initializes connection to the [_secureStorage]
   Future<void> _initStore() async {
-    _secureStorage ??= const FlutterSecureStorage(
-      aOptions: AndroidOptions(encryptedSharedPreferences: true),
-    );
+    _secureStorage ??= const FlutterSecureStorage();
   }
 
+  /// Connects to the websocket
   Future<void> connect() async {
+    final url = "wss://$apiBasePath/ws";
+    log.i("Webocket: $url");
     await _initStore();
     if (_channel != null) return;
 
-    _channel = WebSocketChannel.connect(Uri.parse("wss://$apiBasePath/ws"));
+    _channel = WebSocketChannel.connect(Uri.parse(url));
 
     await _channel!.ready;
     var token = await _secureStorage!.read(key: "token");
@@ -60,11 +82,13 @@ class WebsocketClient {
     }
   }
 
+  /// Disconnects from the websocket
   void _handleDisconnect() {
     sub.cancel();
     _channel = null;
   }
 
+  /// Closes all connections
   void dispose() {
     sub.cancel();
     _channel?.sink.close();
diff --git a/lib/routing/router.dart b/lib/routing/router.dart
index c330f51..fd530ec 100644
--- a/lib/routing/router.dart
+++ b/lib/routing/router.dart
@@ -55,7 +55,7 @@ GoRouter router(AuthRepository authRepository) => GoRouter(
           pageBuilder: (context, state) {
             final viewModel = BalViewModel(
               balRepository: context.read(),
-              id: int.parse(state.pathParameters["id"] ?? ""),
+              selectedBalId: int.parse(state.pathParameters["id"] ?? ""),
               ownerRepository: context.read(),
             );
             return NoTransitionPage(child: BalPage(viewModel: viewModel));
@@ -72,11 +72,6 @@ GoRouter router(AuthRepository authRepository) => GoRouter(
             );
             return NoTransitionPage(child: AddPage(viewModel: viewModel));
           },
-          // routes: [
-          // GoRoute(path: Routes.addForm),
-          // GoRoute(path: Routes.addOwner),
-          // GoRoute(path: Routes.addPrice),
-          // ],
         ),
         GoRoute(
           path: Routes.sell,
diff --git a/lib/ui/add_page/view_model/add_view_model.dart b/lib/ui/add_page/view_model/add_view_model.dart
index 0e685ba..3b0be3a 100644
--- a/lib/ui/add_page/view_model/add_view_model.dart
+++ b/lib/ui/add_page/view_model/add_view_model.dart
@@ -38,18 +38,29 @@ class AddViewModel extends ChangeNotifier {
  * ====================
 */
 
+  /// Owner currently selected in the ui
   Owner? _currentOwner;
+
+  /// Owner currently selected in the ui
   Owner? get currentOwner => _currentOwner;
   set currentOwner(Owner? owner) {
     _currentOwner = owner;
     notifyListeners();
   }
 
-  Owner? _sectionOwner;
-  Owner? get sectionOwner => _sectionOwner;
+  /// Owner of the current user
+  Owner? _ownerOfUser;
 
+  /// Owner of the current user
+  Owner? get ownerOfUser => _ownerOfUser;
+
+  /// All the [Owner]
   List<Owner> _owners = [];
+
+  /// All the [Owner]
   List<Owner>? get owners => _owners;
+
+  /// Adds an owner from it's [firstName], [lastName] and [contact]
   Future<Result<Owner>> addOwner(
     String firstName,
     String lastName,
@@ -85,8 +96,11 @@ class AddViewModel extends ChangeNotifier {
  * =================
 */
 
-  Bal? _currentBal;
-  Bal? get currentBal => _currentBal;
+  /// Ongoing [Bal]
+  Bal? _ongoingBal;
+
+  /// Ongoing [Bal]
+  Bal? get ongoingBal => _ongoingBal;
 
   /*
  * ===================
@@ -94,7 +108,10 @@ class AddViewModel extends ChangeNotifier {
  * ===================
 */
 
+  /// Wether to ask for a price
   bool _askPrice = true;
+
+  /// Wether to ask for a price
   bool get askPrice => _askPrice;
   set askPrice(bool newValue) {
     _askPrice = newValue;
@@ -107,21 +124,25 @@ class AddViewModel extends ChangeNotifier {
  * =================================
 */
 
-  /// Sends an api request with a [bacorde], then gets the [Book] that was
-  /// either created or retrieved. Sens the [Book] back wrapped in a [Result].
-  Future<Result<Book>> scanBook(BarcodeCapture barcode) async {
-    var ean = barcode.barcodes.first.rawValue!;
+  /// Retrieves the book associated with an ean through a [barcode]
+  Future<Result<Book>> scanBook(String ean) async {
     var result = await _bookRepository.getBookByEAN(ean);
     return result;
   }
 
-  Future<Result<BookInstance>> sendBook(
+  /// Creates a new Book Instance from its [book], [owner], [bal] and [price]
+  Future<Result<BookInstance>> sendNewBookInstance(
     Book book,
     Owner owner,
     Bal bal,
     double price,
   ) async {
-    return await _bookInstanceRepository.sendBook(book, owner, bal, price);
+    return await _bookInstanceRepository.sendNewBookInstance(
+      book,
+      owner,
+      bal,
+      price,
+    );
   }
 
   /*
@@ -130,9 +151,11 @@ class AddViewModel extends ChangeNotifier {
  * =================================
 */
 
+  /// Command to load the view model
   late final Command0 load;
   bool isLoaded = false;
 
+  /// Manages the loaders
   Future<Result<void>> _load() async {
     final result1 = await _loadOwners();
     switch (result1) {
@@ -153,11 +176,12 @@ class AddViewModel extends ChangeNotifier {
     return result2;
   }
 
+  /// Loads all necessary data about [Bal]s
   Future<Result<void>> _loadBal() async {
     final result = await _balRepository.getBals();
     switch (result) {
       case Ok():
-        _currentBal = result.value
+        _ongoingBal = result.value
             .where((bal) => bal.state == BalState.ongoing)
             .firstOrNull;
         break;
@@ -168,6 +192,7 @@ class AddViewModel extends ChangeNotifier {
     return result;
   }
 
+  /// Loads all the necessary data about [Owner]s
   Future<Result<void>> _loadOwners() async {
     final result = await _ownerRepository.getOwners();
     switch (result) {
@@ -182,10 +207,10 @@ class AddViewModel extends ChangeNotifier {
         return result;
     }
 
-    final result2 = await _ownerRepository.sectionOwner;
+    final result2 = await _ownerRepository.ownerOfUser;
     switch (result2) {
       case Ok():
-        _sectionOwner = result2.value;
+        _ownerOfUser = result2.value;
         break;
       default:
     }
diff --git a/lib/ui/add_page/widgets/add_page.dart b/lib/ui/add_page/widgets/add_page.dart
index d66e827..e0e68ec 100644
--- a/lib/ui/add_page/widgets/add_page.dart
+++ b/lib/ui/add_page/widgets/add_page.dart
@@ -22,30 +22,27 @@ class AddPage extends StatefulWidget {
 }
 
 class _AddPageState extends State<AddPage> {
-  num? price;
-  final MobileScannerController controller = MobileScannerController(
+  final MobileScannerController scannerController = MobileScannerController(
     formats: [BarcodeFormat.ean13],
     detectionTimeoutMs: 1000,
   );
 
   @override
   void dispose() {
-    controller.dispose();
+    scannerController.dispose();
     super.dispose();
   }
 
   @override
   Widget build(BuildContext context) {
     final theme = Theme.of(context);
-    // return Consumer<TabScreen>(
-    // builder: (context, screen, child) {
     return Scaffold(
       bottomNavigationBar: AppNavigationBar(startIndex: 1),
       body: ListenableBuilder(
         listenable: widget.viewModel,
         builder: (context, child) => switch (widget.viewModel.isLoaded) {
           false => AwaitLoading(),
-          true => switch (widget.viewModel.currentBal) {
+          true => switch (widget.viewModel.ongoingBal) {
             null => Center(
               child: SizedBox(
                 width: 300,
@@ -78,60 +75,37 @@ class _AddPageState extends State<AddPage> {
               children: [
                 ColoredBox(color: Colors.black),
                 MobileScanner(
-                  controller: controller,
+                  controller: scannerController,
                   onDetect: (barcodes) async {
                     if (barcodes.barcodes.isEmpty) {
                       return;
                     }
+
                     if (widget.viewModel.currentOwner == null) {
-                      ScaffoldMessenger.of(context).showSnackBar(
-                        SnackBar(
-                          content: Text(
-                            "Attention : vous devez choisir un·e propriétaire",
-                          ),
-                          behavior: SnackBarBehavior.floating,
-                        ),
+                      _showMissingOwnerSnackBar(
+                        context,
+                        scannerController,
+                        widget.viewModel,
                       );
                       return;
                     }
 
-                    void setPrice(num newPrice) async {
-                      setState(() {
-                        price = newPrice;
-                      });
-                    }
-
-                    Result<Book> result = await widget.viewModel.scanBook(
-                      barcodes,
+                    _scanEan(
+                      context,
+                      widget.viewModel,
+                      barcodes.barcodes.first.rawValue!,
+                      scannerController,
                     );
-
-                    switch (result) {
-                      case Ok():
-                        await _confirmationDialogBuilder(
-                          context,
-                          setPrice,
-                          controller,
-                          widget.viewModel,
-                          result.value,
-                        );
-                        break;
-                      case Error():
-                        ScaffoldMessenger.of(context).showSnackBar(
-                          SnackBar(
-                            content: Text("Erreur : ${result.error}"),
-                            behavior: SnackBarBehavior.floating,
-                          ),
-                        );
-                        break;
-                    }
                   },
                 ),
+
                 Center(
                   child: SvgPicture.asset(
                     'assets/scan-overlay.svg',
                     height: (MediaQuery.sizeOf(context).height / 5) * 2,
                   ),
                 ),
+
                 SafeArea(
                   child: SingleChildScrollView(
                     child: Column(
@@ -155,7 +129,7 @@ class _AddPageState extends State<AddPage> {
                                     ),
                                     onPressed: () => _ownerDialogBuilder(
                                       context,
-                                      controller,
+                                      scannerController,
                                       widget.viewModel,
                                     ),
                                   ),
@@ -184,6 +158,7 @@ class _AddPageState extends State<AddPage> {
                     ),
                   ),
                 ),
+
                 SafeArea(
                   child: Column(
                     mainAxisAlignment: MainAxisAlignment.end,
@@ -197,19 +172,17 @@ class _AddPageState extends State<AddPage> {
                           ),
                           onPressed: () {
                             if (widget.viewModel.currentOwner == null) {
-                              ScaffoldMessenger.of(context).showSnackBar(
-                                SnackBar(
-                                  content: Text(
-                                    "Attention : vous devez choisir un·e propriétaire",
-                                  ),
-                                  behavior: SnackBarBehavior.floating,
-                                ),
+                              _showMissingOwnerSnackBar(
+                                context,
+                                scannerController,
+                                widget.viewModel,
                               );
+                              return;
                             }
 
                             _formDialogBuilder(
                               context,
-                              controller,
+                              scannerController,
                               widget.viewModel,
                             );
                           },
@@ -231,18 +204,71 @@ class _AddPageState extends State<AddPage> {
   }
 }
 
+void _scanEan(
+  BuildContext context,
+  AddViewModel viewModel,
+  String ean,
+  MobileScannerController scannerController, {
+  Function(BuildContext)? leaveLastPopup,
+}) async {
+  Result<Book> result = await viewModel.scanBook(ean);
+
+  if (context.mounted) {
+    if (leaveLastPopup != null) {
+      leaveLastPopup(context);
+    }
+    switch (result) {
+      case Ok():
+        await _confirmationDialogBuilder(
+          context,
+          scannerController,
+          viewModel,
+          result.value,
+        );
+        break;
+      case Error():
+        ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(
+            content: Text("Erreur : ${result.error}"),
+            behavior: SnackBarBehavior.floating,
+          ),
+        );
+        break;
+    }
+  }
+}
+
+void _showMissingOwnerSnackBar(
+  BuildContext context,
+  MobileScannerController scannerController,
+  AddViewModel viewModel,
+) {
+  ScaffoldMessenger.of(context).showSnackBar(
+    SnackBar(
+      content: Text("Attention : vous devez choisir un·e propriétaire"),
+      duration: Duration(seconds: 4),
+      action: SnackBarAction(
+        label: "Choisir",
+        onPressed: () =>
+            _ownerDialogBuilder(context, scannerController, viewModel),
+      ),
+      behavior: SnackBarBehavior.floating,
+    ),
+  );
+}
+
 Future<void> _confirmationDialogBuilder(
   BuildContext context,
-  Function(num) setPrice,
-  MobileScannerController controller,
+  MobileScannerController scannerController,
   AddViewModel viewModel,
   Book book,
 ) {
-  controller.stop();
+  scannerController.stop();
 
+  // Utility function to pass to downwards widgets
   void exitPopup(BuildContext localContext) {
     Navigator.of(localContext).pop();
-    controller.start();
+    scannerController.start();
   }
 
   return showDialog(
@@ -250,7 +276,6 @@ Future<void> _confirmationDialogBuilder(
     barrierDismissible: false,
     builder: (context) => ConfirmationPopup(
       exitPopup: exitPopup,
-      setPrice: setPrice,
       viewModel: viewModel,
       book: book,
     ),
@@ -264,6 +289,7 @@ Future<void> _formDialogBuilder(
 ) {
   controller.stop();
 
+  // Utility function to pass to downwards widgets
   void exitPopup(BuildContext localContext) {
     Navigator.of(localContext).pop();
     controller.start();
@@ -272,7 +298,12 @@ Future<void> _formDialogBuilder(
   return showDialog(
     context: context,
     barrierDismissible: false,
-    builder: (context) => FormPopup(viewModel: viewModel, exitPopup: exitPopup),
+    builder: (context) => FormPopup(
+      viewModel: viewModel,
+      exitPopup: exitPopup,
+      scannerController: controller,
+      scanEan: _scanEan,
+    ),
   );
 }
 
@@ -283,7 +314,8 @@ Future<void> _ownerDialogBuilder(
 ) {
   controller.stop();
 
-  void onPressAccept(BuildContext localContext) {
+  // Utility function to pass to downwards widgets
+  void exitPopup(BuildContext localContext) {
     Navigator.of(localContext).pop();
     controller.start();
   }
@@ -292,6 +324,6 @@ Future<void> _ownerDialogBuilder(
     context: context,
     barrierDismissible: false,
     builder: (context) =>
-        OwnerPopup(viewModel: viewModel, onPressAccept: onPressAccept),
+        OwnerPopup(viewModel: viewModel, exitPopup: exitPopup),
   );
 }
diff --git a/lib/ui/add_page/widgets/confirmation_popup.dart b/lib/ui/add_page/widgets/confirmation_popup.dart
index 980ddee..998e3ea 100644
--- a/lib/ui/add_page/widgets/confirmation_popup.dart
+++ b/lib/ui/add_page/widgets/confirmation_popup.dart
@@ -7,13 +7,11 @@ class ConfirmationPopup extends StatefulWidget {
   const ConfirmationPopup({
     super.key,
     required this.exitPopup,
-    required this.setPrice,
     required this.viewModel,
     required this.book,
   });
 
   final Function(BuildContext) exitPopup;
-  final Function(num) setPrice;
   final AddViewModel viewModel;
   final Book book;
 
@@ -24,9 +22,11 @@ class ConfirmationPopup extends StatefulWidget {
 class _ConfirmationPopupState extends State<ConfirmationPopup> {
   final GlobalKey<FormState> _formKey = GlobalKey<FormState>();
   double price = 0;
+
   @override
   Widget build(BuildContext context) {
     final theme = Theme.of(context);
+
     return AlertDialog(
       title: Text("Prix"),
       content: Form(
@@ -72,6 +72,7 @@ class _ConfirmationPopupState extends State<ConfirmationPopup> {
                   ],
                 ),
               ),
+
               SizedBox(height: 10),
               (widget.viewModel.askPrice)
                   ? TextFormField(
@@ -82,19 +83,26 @@ class _ConfirmationPopupState extends State<ConfirmationPopup> {
                       ),
                       keyboardType: TextInputType.numberWithOptions(
                         decimal: true,
+                        signed: true,
                       ),
                       validator: (value) {
                         if (value == null || value.isEmpty) {
                           return "Indiquez un prix";
-                        } else if (num.tryParse(value) == null) {
+                        } else if (double.tryParse(
+                              value.replaceAll(",", "."),
+                            ) ==
+                            null) {
                           return "Le prix doit être un nombre";
-                        } else if (num.parse(value) < 0) {
+                        } else if (double.parse(value.replaceAll(",", ".")) <
+                            0) {
                           return "Le prix doit être positif ou nul";
                         }
                         return null;
                       },
                       onSaved: (newValue) {
-                        price = double.parse(newValue!);
+                        price = double.parse(
+                          newValue?.replaceAll(",", ".") ?? "0",
+                        );
                       },
                     )
                   : SizedBox(),
@@ -104,6 +112,7 @@ class _ConfirmationPopupState extends State<ConfirmationPopup> {
       ),
       actions: [
         TextButton(
+          child: Text("Annuler"),
           onPressed: () {
             ScaffoldMessenger.of(context).showSnackBar(
               SnackBar(
@@ -113,19 +122,21 @@ class _ConfirmationPopupState extends State<ConfirmationPopup> {
             );
             widget.exitPopup(context);
           },
-          child: Text("Annuler"),
         ),
         TextButton(
+          child: Text("Valider"),
           onPressed: () async {
             if (widget.viewModel.askPrice &&
                 _formKey.currentState!.validate()) {
               _formKey.currentState!.save();
+            } else {
+              return;
             }
 
-            var result = await widget.viewModel.sendBook(
+            var result = await widget.viewModel.sendNewBookInstance(
               widget.book,
               widget.viewModel.currentOwner!,
-              widget.viewModel.currentBal!,
+              widget.viewModel.ongoingBal!,
               price,
             );
 
@@ -135,49 +146,61 @@ class _ConfirmationPopupState extends State<ConfirmationPopup> {
                   Navigator.of(context).pop();
                   showDialog(
                     context: context,
-                    builder: (context) => AlertDialog(
-                      title: Text(
-                        "ID : ${widget.viewModel.currentOwner!.firstName[0].toUpperCase()}${widget.viewModel.currentOwner!.lastName[0].toUpperCase()}${(price == 0) ? "PL" : price.toString()}",
-                      ),
-                      content: Text(
-                        (widget.viewModel.currentOwner!.id ==
-                                widget.viewModel.sectionOwner!.id)
-                            ? "Ce livre appartient à la section. Vous pouvez mettre le code, ou poser une gomette, ..."
-                            : "Identifiant propriétaire de ce livre. Pensez à l'écrire pour retrouver lae propriétaire du livre lors de la vente ou du retour !",
-                      ),
-                      actions: [
-                        TextButton(
-                          onPressed: () {
-                            widget.exitPopup(context);
-                            ScaffoldMessenger.of(context).showSnackBar(
-                              SnackBar(
-                                content: Text(
-                                  "Enregistré: ${widget.book.title}",
-                                ),
-                                behavior: SnackBarBehavior.floating,
-                              ),
-                            );
-                          },
-                          child: Text("Ok"),
-                        ),
-                      ],
-                    ),
+                    barrierDismissible: false,
+                    builder: (context) =>
+                        RegisteredBookPopup(widget: widget, price: price),
                   );
                 }
                 break;
               case Error():
                 if (context.mounted) {
                   ScaffoldMessenger.of(context).showSnackBar(
-                    SnackBar(
-                      content: Text(
-                        "Une erreur est survenue : ${result.error}",
-                      ),
-                    ),
+                    SnackBar(content: Text("Erreur : ${result.error}")),
                   );
                 }
             }
           },
-          child: Text("Valider"),
+        ),
+      ],
+    );
+  }
+}
+
+class RegisteredBookPopup extends StatelessWidget {
+  const RegisteredBookPopup({
+    super.key,
+    required this.widget,
+    required this.price,
+  });
+
+  final ConfirmationPopup widget;
+  final double price;
+
+  @override
+  Widget build(BuildContext context) {
+    return AlertDialog(
+      // This thing is the BookInstance's short ID
+      title: Text(
+        "ID : ${widget.viewModel.currentOwner!.firstName[0].toUpperCase()}${widget.viewModel.currentOwner!.lastName[0].toUpperCase()}${(price == 0) ? "PL" : price.toString()}",
+      ),
+      content: Text(
+        (widget.viewModel.currentOwner!.id == widget.viewModel.ownerOfUser!.id)
+            ? "Pensez à la gomette ! Ce livre appartient au syndicat."
+            : "Identifiant propriétaire de ce livre. Pensez à l'écrire pour retrouver lae propriétaire du livre lors de la vente ou du retour !",
+      ),
+      actions: [
+        TextButton(
+          child: Text("Ok"),
+          onPressed: () {
+            widget.exitPopup(context);
+            ScaffoldMessenger.of(context).showSnackBar(
+              SnackBar(
+                content: Text("Livre enregistré: ${widget.book.title}"),
+                behavior: SnackBarBehavior.floating,
+                duration: Duration(seconds: 2),
+              ),
+            );
+          },
         ),
       ],
     );
diff --git a/lib/ui/add_page/widgets/form_popup.dart b/lib/ui/add_page/widgets/form_popup.dart
index 59368e0..47a3104 100644
--- a/lib/ui/add_page/widgets/form_popup.dart
+++ b/lib/ui/add_page/widgets/form_popup.dart
@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:mobile_scanner/mobile_scanner.dart';
 import 'package:seshat/ui/add_page/view_model/add_view_model.dart';
 
 class FormPopup extends StatelessWidget {
@@ -6,10 +7,14 @@ class FormPopup extends StatelessWidget {
     super.key,
     required this.viewModel,
     required this.exitPopup,
+    required this.scannerController,
+    required this.scanEan,
   });
 
   final AddViewModel viewModel;
   final Function(BuildContext) exitPopup;
+  final MobileScannerController scannerController;
+  final Function scanEan;
 
   @override
   Widget build(BuildContext context) {
@@ -31,6 +36,8 @@ class FormPopup extends StatelessWidget {
                     return _ManualEANPopup(
                       exitPopup: exitPopup,
                       viewModel: viewModel,
+                      scannerController: scannerController,
+                      scanEan: scanEan,
                     );
                   },
                 );
@@ -51,6 +58,7 @@ class FormPopup extends StatelessWidget {
               ),
             ),
           ),
+
           Card(
             clipBehavior: Clip.hardEdge,
             child: InkWell(
@@ -93,11 +101,24 @@ class FormPopup extends StatelessWidget {
   }
 }
 
+/*
+ * ======================
+ * ====< MANUAL EAN >====
+ * ======================
+*/
+
 class _ManualEANPopup extends StatefulWidget {
-  const _ManualEANPopup({required this.exitPopup, required this.viewModel});
+  const _ManualEANPopup({
+    required this.exitPopup,
+    required this.viewModel,
+    required this.scannerController,
+    required this.scanEan,
+  });
 
   final Function(BuildContext) exitPopup;
   final AddViewModel viewModel;
+  final MobileScannerController scannerController;
+  final Function scanEan;
 
   @override
   State<_ManualEANPopup> createState() => _ManualEANPopupState();
@@ -106,11 +127,11 @@ class _ManualEANPopup extends StatefulWidget {
 class _ManualEANPopupState extends State<_ManualEANPopup> {
   final GlobalKey<FormState> _formKey = GlobalKey<FormState>();
   String? ean;
-  num? price;
+
   @override
   Widget build(BuildContext context) {
     return AlertDialog(
-      title: Text("Recherche par EAN"),
+      title: Text("Entrée manuelle par EAN"),
       content: Form(
         key: _formKey,
         child: Column(
@@ -128,61 +149,39 @@ class _ManualEANPopupState extends State<_ManualEANPopup> {
               validator: (value) {
                 if (value == null ||
                     value.length != 13 ||
-                    int.tryParse(value) == null) {
+                    int.tryParse(value) == null ||
+                    int.parse(value) < 0) {
                   return "L'entrée n'est pas un code EAN-13 valide";
                 }
                 return null;
               },
             ),
-            SizedBox(height: 10),
-            ListenableBuilder(
-              listenable: widget.viewModel,
-              builder: (context, child) {
-                return (widget.viewModel.askPrice)
-                    ? TextFormField(
-                        decoration: InputDecoration(
-                          labelText: "Prix",
-                          border: OutlineInputBorder(),
-                          suffixText: "€",
-                        ),
-                        keyboardType: TextInputType.numberWithOptions(
-                          decimal: true,
-                        ),
-                        validator: (value) {
-                          if (value == null || value.isEmpty) {
-                            return "Indiquez un prix";
-                          } else if (num.tryParse(value) == null) {
-                            return "Le prix doit être un nombre";
-                          } else if (num.parse(value) < 0) {
-                            return "Le prix doit être positif ou nul";
-                          }
-                          return null;
-                        },
-                        onSaved: (newValue) {
-                          price = num.parse(newValue!);
-                        },
-                      )
-                    : SizedBox();
-              },
-            ),
           ],
         ),
       ),
       actions: [
         TextButton(
+          child: Text("Annuler"),
           onPressed: () {
             widget.exitPopup(context);
           },
-          child: Text("Annuler"),
         ),
         TextButton(
+          child: Text("Valider"),
           onPressed: () {
             if (_formKey.currentState!.validate()) {
               _formKey.currentState!.save();
-              widget.exitPopup(context);
+              widget.scanEan(
+                context,
+                widget.viewModel,
+                ean!,
+                widget.scannerController,
+                leaveLastPopup: (context) {
+                  Navigator.of(context).pop();
+                },
+              );
             }
           },
-          child: Text("Valider"),
         ),
       ],
     );
@@ -279,6 +278,7 @@ class _FullyManualState extends State<_FullyManual> {
                         ),
                         keyboardType: TextInputType.numberWithOptions(
                           decimal: true,
+                          signed: true,
                         ),
                         validator: (value) {
                           if (value == null || value.isEmpty) {
diff --git a/lib/ui/add_page/widgets/owner_popup.dart b/lib/ui/add_page/widgets/owner_popup.dart
index 35fe4b3..8627c13 100644
--- a/lib/ui/add_page/widgets/owner_popup.dart
+++ b/lib/ui/add_page/widgets/owner_popup.dart
@@ -6,11 +6,11 @@ class OwnerPopup extends StatefulWidget {
   const OwnerPopup({
     super.key,
     required this.viewModel,
-    required this.onPressAccept,
+    required this.exitPopup,
   });
 
   final AddViewModel viewModel;
-  final Function(BuildContext) onPressAccept;
+  final Function(BuildContext) exitPopup;
 
   @override
   State<OwnerPopup> createState() => _OwnerPopupState();
@@ -166,7 +166,7 @@ class _OwnerPopupState extends State<OwnerPopup> {
                   });
                 }
               }
-              widget.onPressAccept(context);
+              widget.exitPopup(context);
             },
             child: Text(
               (!showNewOwner && searchController.text == "")
diff --git a/lib/ui/auth/viewmodel/login_view_model.dart b/lib/ui/auth/viewmodel/login_view_model.dart
index 190ea46..51179f0 100644
--- a/lib/ui/auth/viewmodel/login_view_model.dart
+++ b/lib/ui/auth/viewmodel/login_view_model.dart
@@ -13,8 +13,10 @@ class LoginViewModel extends ChangeNotifier {
 
   final AuthRepository _authRepository;
 
+  /// Command to login with added capabilities
   late Command1 login;
 
+  /// Logins the user with credentials [(String username, String password)]
   Future<Result<void>> _login((String, String) credentials) async {
     final (username, password) = credentials;
     final result = await _authRepository.login(username, password);
@@ -27,10 +29,12 @@ class LoginViewModel extends ChangeNotifier {
  * =================================
 */
 
+  /// Loads all necessary data
   late final Command0 load;
   bool isLoaded = false;
   bool isUpToDate = false;
 
+  /// Manages loaders
   Future<Result<void>> _load() async {
     final result1 = await _loadApiVersion();
     switch (result1) {
@@ -44,6 +48,7 @@ class LoginViewModel extends ChangeNotifier {
     return result1;
   }
 
+  /// Loads the current remote api version and compares to local hardcoded [apiVersion]
   Future<Result<void>> _loadApiVersion() async {
     final result = await _authRepository.getRemoteApiVersion();
     switch (result) {
diff --git a/lib/ui/bal_page/view_model/bal_view_model.dart b/lib/ui/bal_page/view_model/bal_view_model.dart
index f9947f1..c3cdbb9 100644
--- a/lib/ui/bal_page/view_model/bal_view_model.dart
+++ b/lib/ui/bal_page/view_model/bal_view_model.dart
@@ -14,7 +14,7 @@ import 'package:seshat/utils/result.dart';
 class BalViewModel extends ChangeNotifier {
   BalViewModel({
     required BalRepository balRepository,
-    required this.id,
+    required this.selectedBalId,
     required OwnerRepository ownerRepository,
   }) : _balRepository = balRepository,
        _ownerRepository = ownerRepository {
@@ -30,31 +30,50 @@ class BalViewModel extends ChangeNotifier {
  * =====================
 */
 
-  Bal? _bal;
-  int id;
-  Bal? get bal => _bal;
+  /// Selected [Bal]
+  Bal? _selectedBal;
+
+  /// Selected [Bal]
+  Bal? get selectedBal => _selectedBal;
+
+  /// Selected [Bal.id] from path parameters
+  int selectedBalId;
+
+  /// Is one of the [Bal] [BalState.ongoing]
   bool isABalOngoing = false;
 
-  Future<Result<void>> stopBal(int id) async {
-    final result = await _balRepository.stopBal(id);
+  /// Stops a [Bal]
+  Future<Result<void>> stopBal(int balId) async {
+    isLoaded = false;
+    notifyListeners();
+    final result = await _balRepository.stopBal(balId);
     switch (result) {
       case Ok():
-        _bal = result.value;
-        notifyListeners();
+        _selectedBal = result.value;
         break;
       default:
     }
+    final result2 = await _loadEnded();
+    switch (result2) {
+      case Ok():
+        isLoaded = true;
+        break;
+      case Error():
+        break;
+    }
+    notifyListeners();
     return result;
   }
 
-  Future<Result<void>> startBal(int id) async {
+  /// Starts a [Bal]
+  Future<Result<void>> startBal(int balId) async {
     if (isABalOngoing) {
       return Result.error(Exception("Cannot have multiple BALs ongoing !"));
     }
-    final result = await _balRepository.startBal(id);
+    final result = await _balRepository.startBal(balId);
     switch (result) {
       case Ok():
-        _bal = result.value;
+        _selectedBal = result.value;
         notifyListeners();
         break;
       default:
@@ -62,21 +81,20 @@ class BalViewModel extends ChangeNotifier {
     return result;
   }
 
+  /// Edits a [Bal]'s [name], [startTime] or [endTime]
   Future<Result<void>> editBal(
     int id,
     String name,
-    DateTime start,
-    DateTime end,
+    DateTime startTime,
+    DateTime endTime,
   ) async {
-    final result = await _balRepository.editBal(id, name, start, end);
+    final result = await _balRepository.editBal(id, name, startTime, endTime);
     switch (result) {
       case Ok():
-        debugPrint("\n\n\n\nDID EDIT\n\n\n\n");
-        _bal = result.value;
+        _selectedBal = result.value;
         notifyListeners();
         break;
       case Error():
-        debugPrint("\n\n\n\nERROR: ${result.error}");
         break;
     }
     return result;
@@ -89,11 +107,16 @@ class BalViewModel extends ChangeNotifier {
 */
 
   // Specific to ended state
+
+  /// Owners a book or money is owed to
   List<ReturnOwner>? owedToOwners;
-  double? totalOwed;
+
+  /// Statistics about the [_selectedBal]
   BalStats? stats;
 
-  Future<void> applyAccountingOwners(
+  /// Froms [books], updates [owners] to include all the necessary information
+  /// See [the api doc](https://bal.ueauvergne.fr/docs/#/bal-api/get_bal_accounting) for more details
+  Future<void> _updateOwedToOwnersWithBooks(
     List<ReturnOwner> owners,
     Map<String, Book> books,
   ) async {
@@ -114,15 +137,20 @@ class BalViewModel extends ChangeNotifier {
     }
   }
 
+  /// Returns either Books, Money or All ([ReturnType]) to an [Owner]
   Future<Result<void>> returnById(ReturnType type, int ownerId) async {
-    final result = await _balRepository.returnToId(id, ownerId, type);
-    final result2 = await _balRepository.getAccounting(id);
+    final result = await _balRepository.returnToId(
+      selectedBalId,
+      ownerId,
+      type,
+    );
+    final result2 = await _balRepository.getAccounting(selectedBalId);
     switch (result2) {
       case Ok():
-        applyAccountingOwners(result2.value.owners, result2.value.books);
+        _updateOwedToOwnersWithBooks(result2.value.owners, result2.value.books);
         break;
       case Error():
-        debugPrint(result2.error.toString());
+        break;
     }
     notifyListeners();
     return result;
@@ -134,31 +162,31 @@ class BalViewModel extends ChangeNotifier {
  * =================================
 */
 
+  /// Loads all the necessary information
   late final Command0 load;
   bool isLoaded = false;
 
+  /// Manages loaders
   Future<Result<void>> _load() async {
     isABalOngoing = _balRepository.isABalOngoing();
     final result1 = await _loadBal();
     switch (result1) {
       case Ok():
-        isLoaded = (_bal == null || _bal?.state != BalState.ended)
+        isLoaded =
+            (_selectedBal == null || _selectedBal?.state != BalState.ended)
             ? true
             : false;
         break;
       default:
         break;
     }
-    debugPrint("$isLoaded");
-    if (_bal?.state == BalState.ended) {
+    if (_selectedBal?.state == BalState.ended) {
       final result2 = await _loadEnded();
-      debugPrint("Hello");
       switch (result2) {
         case Ok():
           isLoaded = true;
           break;
         case Error():
-          debugPrint("No ${result2.error}");
           break;
       }
     }
@@ -166,11 +194,12 @@ class BalViewModel extends ChangeNotifier {
     return result1;
   }
 
+  /// Loads all common [Bal] information
   Future<Result<void>> _loadBal() async {
-    final result = await _balRepository.balById(id);
+    final result = await _balRepository.balById(selectedBalId);
     switch (result) {
       case Ok():
-        _bal = result.value;
+        _selectedBal = result.value;
         break;
       case Error():
         break;
@@ -179,15 +208,16 @@ class BalViewModel extends ChangeNotifier {
     return result;
   }
 
+  /// Loads [Bal] information when it is [BalState.ended]
   Future<Result<void>> _loadEnded() async {
-    final result = await _balRepository.getAccountingNoCache(id);
+    final result = await _balRepository.getAccountingNoCache(selectedBalId);
     switch (result) {
       case Ok():
-        applyAccountingOwners(result.value.owners, result.value.books);
+        _updateOwedToOwnersWithBooks(result.value.owners, result.value.books);
         break;
       default:
     }
-    final result2 = await _balRepository.getBalStats(id);
+    final result2 = await _balRepository.getBalStats(selectedBalId);
     switch (result2) {
       case Ok():
         stats = result2.value;
diff --git a/lib/ui/bal_page/widget/bal_page.dart b/lib/ui/bal_page/widget/bal_page.dart
index 2347dc3..e7e3467 100644
--- a/lib/ui/bal_page/widget/bal_page.dart
+++ b/lib/ui/bal_page/widget/bal_page.dart
@@ -27,14 +27,14 @@ class _BalPageState extends State<BalPage> {
             bottomNavigationBar: AppNavigationBar(startIndex: 0),
             body: AwaitLoading(),
           ),
-          true => switch (widget.viewModel.bal == null) {
+          true => switch (widget.viewModel.selectedBal == null) {
             true => Scaffold(
               bottomNavigationBar: AppNavigationBar(startIndex: 0),
               body: Center(
                 child: Text("La BAL référencée n'est pas accessible"),
               ),
             ),
-            false => switch (widget.viewModel.bal!.state) {
+            false => switch (widget.viewModel.selectedBal!.state) {
               BalState.pending => BalPendingScreen(viewModel: widget.viewModel),
               BalState.ongoing => BalOngoingScreen(viewModel: widget.viewModel),
               BalState.ended => BalEndedScreen(viewModel: widget.viewModel),
diff --git a/lib/ui/bal_page/widget/ended/bal_ended_screen.dart b/lib/ui/bal_page/widget/ended/bal_ended_screen.dart
index 70a9905..2b62688 100644
--- a/lib/ui/bal_page/widget/ended/bal_ended_screen.dart
+++ b/lib/ui/bal_page/widget/ended/bal_ended_screen.dart
@@ -30,12 +30,15 @@ class _BalEndedScreenState extends State<BalEndedScreen>
     return Scaffold(
       bottomNavigationBar: AppNavigationBar(startIndex: 0),
       appBar: AppBar(
-        title: Text(widget.viewModel.bal!.name),
+        title: Text(widget.viewModel.selectedBal!.name),
         bottom: TabBar(
           controller: tabController,
           tabs: [
             Tab(text: "Statistiques"),
-            Tab(text: "À rendre"),
+            Tab(
+              text:
+                  "À rendre (${widget.viewModel.owedToOwners?.length.toString() ?? "0"})",
+            ),
           ],
         ),
       ),
diff --git a/lib/ui/bal_page/widget/ongoing/bal_ongoing_screen.dart b/lib/ui/bal_page/widget/ongoing/bal_ongoing_screen.dart
index a9ca41e..db9fd01 100644
--- a/lib/ui/bal_page/widget/ongoing/bal_ongoing_screen.dart
+++ b/lib/ui/bal_page/widget/ongoing/bal_ongoing_screen.dart
@@ -11,7 +11,7 @@ class BalOngoingScreen extends StatelessWidget {
   Widget build(BuildContext context) {
     return Scaffold(
       bottomNavigationBar: AppNavigationBar(startIndex: 0),
-      appBar: AppBar(title: Text(viewModel.bal!.name)),
+      appBar: AppBar(title: Text(viewModel.selectedBal!.name)),
       body: Padding(
         padding: const EdgeInsets.all(10.0),
         child: Column(
@@ -38,7 +38,9 @@ class BalOngoingScreen extends StatelessWidget {
                           ),
                           TextButton(
                             onPressed: () async {
-                              await viewModel.stopBal(viewModel.bal!.id);
+                              await viewModel.stopBal(
+                                viewModel.selectedBal!.id,
+                              );
                               if (context.mounted) {
                                 Navigator.of(context).pop();
                               }
diff --git a/lib/ui/bal_page/widget/pending/bal_pending_screen.dart b/lib/ui/bal_page/widget/pending/bal_pending_screen.dart
index 2e57c22..e5d7164 100644
--- a/lib/ui/bal_page/widget/pending/bal_pending_screen.dart
+++ b/lib/ui/bal_page/widget/pending/bal_pending_screen.dart
@@ -15,7 +15,7 @@ class BalPendingScreen extends StatelessWidget {
     return Scaffold(
       bottomNavigationBar: AppNavigationBar(startIndex: 0),
       appBar: AppBar(
-        title: Text(viewModel.bal!.name),
+        title: Text(viewModel.selectedBal!.name),
         actions: [
           IconButton(
             onPressed: () {
@@ -57,7 +57,9 @@ class BalPendingScreen extends StatelessWidget {
                           ),
                           TextButton(
                             onPressed: () async {
-                              await viewModel.startBal(viewModel.bal!.id);
+                              await viewModel.startBal(
+                                viewModel.selectedBal!.id,
+                              );
                               if (context.mounted) {
                                 Navigator.of(context).pop();
                               }
@@ -96,8 +98,8 @@ class _EditPopup extends State<EditPopup> {
       firstDate: DateTime(DateTime.now().year - 1),
       lastDate: DateTime(DateTime.now().year + 2),
       initialDateRange: DateTimeRange(
-        start: start ?? widget.viewModel.bal!.startTime,
-        end: end ?? widget.viewModel.bal!.endTime,
+        start: start ?? widget.viewModel.selectedBal!.startTime,
+        end: end ?? widget.viewModel.selectedBal!.endTime,
       ),
     );
 
@@ -126,7 +128,7 @@ class _EditPopup extends State<EditPopup> {
                     labelText: "Nom de la BAL",
                     border: OutlineInputBorder(),
                   ),
-                  initialValue: widget.viewModel.bal!.name,
+                  initialValue: widget.viewModel.selectedBal!.name,
                   validator: (value) {
                     if (value == null || value.isEmpty) {
                       return "Veuillez entrer un nom";
@@ -169,7 +171,7 @@ class _EditPopup extends State<EditPopup> {
             if (_formKey.currentState!.validate()) {
               _formKey.currentState!.save();
 
-              final Bal bal = widget.viewModel.bal!;
+              final Bal bal = widget.viewModel.selectedBal!;
 
               final result = await widget.viewModel.editBal(
                 bal.id,
diff --git a/lib/ui/home_page/view_model/home_view_model.dart b/lib/ui/home_page/view_model/home_view_model.dart
index 29ffeda..e6b68d2 100644
--- a/lib/ui/home_page/view_model/home_view_model.dart
+++ b/lib/ui/home_page/view_model/home_view_model.dart
@@ -18,18 +18,25 @@ class HomeViewModel extends ChangeNotifier {
  * =================
 */
 
+  /// [List<Bal>] of all [Bal]
   List<Bal> _bals = [];
+
+  /// [List<Bal>] of all [Bal]
   List<Bal> get bals => _bals;
 
-  Bal? _currentBal;
-  Bal? get currentBal => _currentBal;
+  /// [Bal] currently [BalState.ongoing]
+  Bal? _ongoingBal;
 
+  /// [Bal] currently [BalState.ongoing]
+  Bal? get ongoingBal => _ongoingBal;
+
+  /// Creates a [Bal] from its [name], [startTime] and [endTime]
   Future<Result<void>> createBal(
     String name,
-    DateTime start,
-    DateTime end,
+    DateTime startTime,
+    DateTime endTime,
   ) async {
-    final result = await _balRepository.addBal(name, start, end);
+    final result = await _balRepository.addBal(name, startTime, endTime);
     switch (result) {
       case Ok():
         final result2 = await _balRepository.getBals();
@@ -54,9 +61,11 @@ class HomeViewModel extends ChangeNotifier {
  * =================================
 */
 
+  /// Command to load all necessary data
   late final Command0 load;
   bool isLoaded = false;
 
+  /// Manages loaders
   Future<Result<void>> _load() async {
     final result2 = await _loadBal();
     switch (result2) {
@@ -70,12 +79,13 @@ class HomeViewModel extends ChangeNotifier {
     return result2;
   }
 
+  /// Loads data about [Bal]
   Future<Result<void>> _loadBal() async {
     final result = await _balRepository.getBals();
     switch (result) {
       case Ok():
         _bals = result.value..sort((a, b) => a.compareTo(b));
-        _currentBal = _bals
+        _ongoingBal = _bals
             .where((bal) => bal.state == BalState.ongoing)
             .firstOrNull;
         break;
diff --git a/lib/ui/home_page/widgets/home_page.dart b/lib/ui/home_page/widgets/home_page.dart
index adc6684..2f56dbd 100644
--- a/lib/ui/home_page/widgets/home_page.dart
+++ b/lib/ui/home_page/widgets/home_page.dart
@@ -38,7 +38,7 @@ class _HomePageState extends State<HomePage> {
                       : ListView(
                           children: [
                             for (Bal bal in widget.viewModel.bals.where(
-                              (el) => el.id != widget.viewModel.currentBal?.id,
+                              (el) => el.id != widget.viewModel.ongoingBal?.id,
                             ))
                               Padding(
                                 padding: const EdgeInsets.symmetric(
@@ -81,20 +81,20 @@ class _HomePageState extends State<HomePage> {
                           ],
                         ),
                 ),
-                switch (widget.viewModel.currentBal == null) {
+                switch (widget.viewModel.ongoingBal == null) {
                   true => SizedBox(),
                   false => Padding(
                     padding: const EdgeInsets.symmetric(horizontal: 10.0),
                     child: Card(
                       child: ListTile(
                         leading: Icon(Icons.event_available),
-                        title: Text(widget.viewModel.currentBal!.name),
+                        title: Text(widget.viewModel.ongoingBal!.name),
                         subtitle: Text("BAL en cours"),
                         trailing: IconButton(
                           onPressed: () {
                             _moveToBal(
                               context,
-                              widget.viewModel.currentBal!.id,
+                              widget.viewModel.ongoingBal!.id,
                             );
                           },
                           icon: Icon(Icons.arrow_forward),
diff --git a/lib/ui/sell_page/view_model/sell_view_model.dart b/lib/ui/sell_page/view_model/sell_view_model.dart
index 549b328..77b0393 100644
--- a/lib/ui/sell_page/view_model/sell_view_model.dart
+++ b/lib/ui/sell_page/view_model/sell_view_model.dart
@@ -31,10 +31,13 @@ class SellViewModel extends ChangeNotifier {
   final BookRepository _bookRepository;
   final OwnerRepository _ownerRepository;
 
-  bool _showScan = false;
-  bool get showScan => _showScan;
-  set showScan(bool newValue) {
-    _showScan = newValue;
+  /// Wether to show the scan screen
+  bool _showScanScreen = false;
+
+  /// Wether to show the scan screen
+  bool get showScanScreen => _showScanScreen;
+  set showScanScreen(bool newValue) {
+    _showScanScreen = newValue;
     notifyListeners();
   }
 
@@ -44,56 +47,66 @@ class SellViewModel extends ChangeNotifier {
  * ===============================
 */
 
-  final List<BookStack> _soldBooks = [];
-  List<BookStack> get soldBooks => _soldBooks;
+  /// Books in the sell
+  final List<BookStack> _booksInSell = [];
 
+  /// Books in the sell
+  List<BookStack> get booksInSell => _booksInSell;
+
+  /// Books scanned on the scan screen
   final List<BookStack> _scannedBooks = [];
+
+  /// Books scanned on the scan screen
   List<BookStack> get scannedBooks => _scannedBooks;
 
   bool isScanLoaded = false;
   bool isSendingSell = false;
-  double minimumAmount = 0;
+  double minimumAmountToPay = 0;
 
-  void sellBook(BookStack addedBook) {
-    minimumAmount += addedBook.instance.price;
-    _soldBooks.add(addedBook);
+  /// Adds a book to the [_booksInSell]
+  void addBookToSell(BookStack bookToAdd) {
+    minimumAmountToPay += bookToAdd.instance.price;
+    _booksInSell.add(bookToAdd);
     notifyListeners();
   }
 
-  void sendSell(double givenAmount) async {
+  /// Sends the sell
+  void sendSell(double givenMoney) async {
     isSendingSell = true;
     notifyListeners();
-    List<BookInstance> toSend = [];
-    int nbOfPl = 0;
-    for (BookStack book in _soldBooks) {
+    List<BookInstance> booksToSend = [];
+    int numberOfPL = 0;
+    for (BookStack book in _booksInSell) {
       if (book.instance.price != 0) {
         book.instance.soldPrice = book.instance.price;
-        givenAmount -= book.instance.price;
-        toSend.add(book.instance);
+        givenMoney -= book.instance.price;
+        booksToSend.add(book.instance);
       } else {
-        nbOfPl++;
+        numberOfPL++;
       }
     }
-    if (nbOfPl != 0) {
-      double amountPerPl = givenAmount / nbOfPl;
-      for (BookStack book in _soldBooks) {
+    if (numberOfPL != 0) {
+      double moneyPerPL = givenMoney / numberOfPL;
+      for (BookStack book in _booksInSell) {
         if (book.instance.price == 0) {
-          book.instance.soldPrice = amountPerPl;
-          toSend.add(book.instance);
+          book.instance.soldPrice = moneyPerPL;
+          booksToSend.add(book.instance);
         }
       }
     }
-    await _bookInstanceRepository.sellBooks(toSend);
-    _soldBooks.clear();
+    await _bookInstanceRepository.sellBooks(booksToSend);
+    _booksInSell.clear();
     isSendingSell = false;
     notifyListeners();
   }
 
-  void deleteBook(int id) {
-    _soldBooks.removeWhere((book) => book.instance.id == id);
+  /// Removes a book from the sell
+  void removeBookFromSell(int bookId) {
+    _booksInSell.removeWhere((book) => book.instance.id == bookId);
     notifyListeners();
   }
 
+  /// Search a book by [title] or [author]
   Future<void> searchBook(String title, String author) async {
     Bal? bal = await _balRepository.ongoingBal();
     isScanLoaded = false;
@@ -106,15 +119,21 @@ class SellViewModel extends ChangeNotifier {
     );
     switch (result) {
       case Ok():
+        // For each result value, you need to complete some values
         for (SearchResult searchResult in result.value) {
+          // In case you get a book that's actually not available
           if (searchResult.instance.available == false) {
             continue;
           }
-          if (_soldBooks
+
+          // In case the instance is already in the sell
+          if (_booksInSell
               .where((book) => book.instance.id == searchResult.instance.id)
               .isNotEmpty) {
             continue;
           }
+
+          // Search for the owner
           Owner owner;
           final result2 = await _ownerRepository.getOwnerById(
             searchResult.instance.ownerId,
@@ -126,6 +145,7 @@ class SellViewModel extends ChangeNotifier {
             case Error():
               continue;
           }
+
           _scannedBooks.add(
             BookStack(searchResult.book, searchResult.instance, owner),
           );
@@ -140,18 +160,19 @@ class SellViewModel extends ChangeNotifier {
     return;
   }
 
+  /// Gets [BookInstance]s from its ean in a [barcode]
   Future<void> scanBook(BarcodeCapture barcode) async {
     isScanLoaded = false;
     int ean = int.parse(barcode.barcodes.first.rawValue!);
-    Bal? bal = await _balRepository.ongoingBal();
+    Bal? ongoingBal = await _balRepository.ongoingBal();
     _scannedBooks.clear();
 
-    final result = await _bookInstanceRepository.getByEan(bal!.id, ean);
-    switch (result) {
+    final result1 = await _bookInstanceRepository.getByEan(ongoingBal!.id, ean);
+    switch (result1) {
       case Ok():
         Book book;
         final result2 = await _bookRepository.getBookById(
-          result.value.first.bookId,
+          result1.value.first.bookId,
         );
         switch (result2) {
           case Ok():
@@ -160,15 +181,22 @@ class SellViewModel extends ChangeNotifier {
           case Error():
             return;
         }
-        for (BookInstance instance in result.value) {
+
+        // For each result value, you need to complete some values
+        for (BookInstance instance in result1.value) {
+          // In case you get a book that's actually not available
           if (instance.available == false) {
             continue;
           }
-          if (_soldBooks
+
+          // In case the instance is already in the sell
+          if (_booksInSell
               .where((book) => book.instance.id == instance.id)
               .isNotEmpty) {
             continue;
           }
+
+          // Search for the owner
           Owner owner;
           final result3 = await _ownerRepository.getOwnerById(instance.ownerId);
           switch (result3) {
@@ -178,6 +206,7 @@ class SellViewModel extends ChangeNotifier {
             case Error():
               continue;
           }
+
           _scannedBooks.add(BookStack(book, instance, owner));
         }
         break;
@@ -196,8 +225,11 @@ class SellViewModel extends ChangeNotifier {
  * =================
 */
 
-  Bal? _currentBal;
-  get currentBal => _currentBal;
+  /// The currently ongoing [Bal]
+  Bal? _ongoingBal;
+
+  /// The currently ongoing [Bal]
+  get ongoingBal => _ongoingBal;
 
   /*
  * =================================
@@ -205,9 +237,11 @@ class SellViewModel extends ChangeNotifier {
  * =================================
 */
 
+  /// Command to load necessary data
   late final Command0 load;
   bool isLoaded = false;
 
+  /// Manages loaders
   Future<Result<void>> _load() async {
     final result1 = await _loadBal();
     switch (result1) {
@@ -221,11 +255,12 @@ class SellViewModel extends ChangeNotifier {
     return result1;
   }
 
+  /// Loads information about [Bal]
   Future<Result<void>> _loadBal() async {
     final result = await _balRepository.getBals();
     switch (result) {
       case Ok():
-        _currentBal = result.value
+        _ongoingBal = result.value
             .where((bal) => bal.state == BalState.ongoing)
             .firstOrNull;
         break;
diff --git a/lib/ui/sell_page/widgets/scan_screen.dart b/lib/ui/sell_page/widgets/scan_screen.dart
index ceb9920..3036fb8 100644
--- a/lib/ui/sell_page/widgets/scan_screen.dart
+++ b/lib/ui/sell_page/widgets/scan_screen.dart
@@ -65,7 +65,7 @@ class _ScanScreenState extends State<ScanScreen> {
             children: [
               IconButton(
                 onPressed: () {
-                  widget.viewModel.showScan = false;
+                  widget.viewModel.showScanScreen = false;
                 },
                 icon: Icon(Icons.arrow_back),
               ),
diff --git a/lib/ui/sell_page/widgets/sell_choice_popup.dart b/lib/ui/sell_page/widgets/sell_choice_popup.dart
index 1931a86..f96bb93 100644
--- a/lib/ui/sell_page/widgets/sell_choice_popup.dart
+++ b/lib/ui/sell_page/widgets/sell_choice_popup.dart
@@ -34,9 +34,9 @@ class SellChoicePopup extends StatelessWidget {
                       child: Card(
                         child: InkWell(
                           onTap: () {
-                            viewModel.sellBook(book);
+                            viewModel.addBookToSell(book);
                             Navigator.of(context).pop();
-                            viewModel.showScan = false;
+                            viewModel.showScanScreen = false;
                           },
                           child: ListTile(
                             leading: Text(
diff --git a/lib/ui/sell_page/widgets/sell_page.dart b/lib/ui/sell_page/widgets/sell_page.dart
index 0ae364e..784ff23 100644
--- a/lib/ui/sell_page/widgets/sell_page.dart
+++ b/lib/ui/sell_page/widgets/sell_page.dart
@@ -28,7 +28,7 @@ class _SellPageState extends State<SellPage> {
         builder: (context, child) {
           return switch (widget.viewModel.isLoaded) {
             false => AwaitLoading(),
-            true => switch (widget.viewModel.currentBal) {
+            true => switch (widget.viewModel.ongoingBal) {
               null => Center(
                 child: SizedBox(
                   width: 300,
@@ -80,7 +80,7 @@ class _SellPageState extends State<SellPage> {
                                         ? Center(child: Text("Aucun"))
                                         : SizedBox(),
                                     for (BookStack book
-                                        in widget.viewModel.soldBooks)
+                                        in widget.viewModel.booksInSell)
                                       Padding(
                                         padding: const EdgeInsets.symmetric(
                                           horizontal: 15,
@@ -99,9 +99,10 @@ class _SellPageState extends State<SellPage> {
                                             ),
                                             trailing: IconButton(
                                               onPressed: () {
-                                                widget.viewModel.deleteBook(
-                                                  book.instance.id,
-                                                );
+                                                widget.viewModel
+                                                    .removeBookFromSell(
+                                                      book.instance.id,
+                                                    );
                                               },
                                               icon: Icon(Icons.delete),
                                             ),
@@ -113,7 +114,7 @@ class _SellPageState extends State<SellPage> {
                         ),
                         SizedBox(height: 40),
                         Text(
-                          "Montant minimum à payer : ${widget.viewModel.minimumAmount.toString()}€",
+                          "Montant minimum à payer : ${widget.viewModel.minimumAmountToPay.toString()}€",
                         ),
                         Padding(
                           padding: const EdgeInsets.symmetric(horizontal: 60.0),
@@ -122,7 +123,6 @@ class _SellPageState extends State<SellPage> {
                               controller: price,
                               decoration: InputDecoration(
                                 labelText: "Argent reçu",
-                                hintText: "Les décimales sont avec des .",
                                 helperText:
                                     "L'argent reçu sera réparti automatiquement.",
                                 suffixText: "€",
@@ -130,6 +130,7 @@ class _SellPageState extends State<SellPage> {
                               ),
                               keyboardType: TextInputType.numberWithOptions(
                                 decimal: true,
+                                signed: true,
                               ),
                             ),
                           ),
@@ -140,7 +141,21 @@ class _SellPageState extends State<SellPage> {
                           children: [
                             IconButton(
                               onPressed: () {
-                                if (double.tryParse(price.text) == null) {
+                                if (widget.viewModel.scannedBooks.isEmpty) {
+                                  ScaffoldMessenger.of(context).showSnackBar(
+                                    SnackBar(
+                                      content: Text(
+                                        "La vente doit comporter au moins un livre",
+                                      ),
+                                      behavior: SnackBarBehavior.floating,
+                                    ),
+                                  );
+                                  return;
+                                }
+                                if (double.tryParse(
+                                      price.text.replaceFirst(",", "."),
+                                    ) ==
+                                    null) {
                                   ScaffoldMessenger.of(context).showSnackBar(
                                     SnackBar(
                                       content: Text(
@@ -150,8 +165,10 @@ class _SellPageState extends State<SellPage> {
                                     ),
                                   );
                                   return;
-                                } else if (double.parse(price.text) <
-                                    widget.viewModel.minimumAmount) {
+                                } else if (double.parse(
+                                      price.text.replaceFirst(",", "."),
+                                    ) <
+                                    widget.viewModel.minimumAmountToPay) {
                                   ScaffoldMessenger.of(context).showSnackBar(
                                     SnackBar(
                                       content: Text(
@@ -163,7 +180,9 @@ class _SellPageState extends State<SellPage> {
                                   return;
                                 }
                                 widget.viewModel.sendSell(
-                                  double.parse(price.text),
+                                  double.parse(
+                                    price.text.replaceFirst(",", "."),
+                                  ),
                                 );
                                 ScaffoldMessenger.of(context).showSnackBar(
                                   SnackBar(
@@ -184,7 +203,7 @@ class _SellPageState extends State<SellPage> {
                             SizedBox(width: 70),
                             IconButton(
                               onPressed: () {
-                                widget.viewModel.showScan = true;
+                                widget.viewModel.showScanScreen = true;
                               },
                               icon: Icon(Icons.add),
                               style: ButtonStyle(
@@ -198,7 +217,7 @@ class _SellPageState extends State<SellPage> {
                       ],
                     ),
                   ),
-                  (widget.viewModel.showScan)
+                  (widget.viewModel.showScanScreen)
                       ? ScanScreen(viewModel: widget.viewModel)
                       : SizedBox(),
                 ],