diff --git a/BookAStar/BookAStar/App.xaml b/BookAStar/BookAStar/App.xaml
index 617bae21..926c83f0 100644
--- a/BookAStar/BookAStar/App.xaml
+++ b/BookAStar/BookAStar/App.xaml
@@ -24,6 +24,7 @@
       
 
       <Color x:Key="BackgroundColor">#30AAAAFA</Color>
+      <Color x:Key="LabelBackgroundColor">#30FAFAFA</Color>
       <Color x:Key="OddColor">#207AFAFA</Color>
       <Color x:Key="TextColor">#FF103010</Color>
       <Color x:Key="LabelColor">#FF303010</Color>
@@ -44,8 +45,11 @@
       </Style>
       
       <Style x:Key="LabelStyle" TargetType="Label">
-        <Setter Property="TextColor" Value="{StaticResource TextColor}" />
+        <Setter Property="TextColor" Value="{StaticResource LabelColor}" />
+        <Setter Property="BackgroundColor" Value="{StaticResource LabelBackgroundColor}" />
+        
         <Setter Property="LineBreakMode" Value="WordWrap" />
+        <Setter Property="Margin" Value="2,4,2,4" />
       </Style>
 
       <Style x:Key="BigLabel"  BasedOn="{StaticResource LabelStyle}" TargetType="Label">
@@ -73,8 +77,8 @@
         <Setter Property="HorizontalOptions" Value="Center" />
         <Setter Property="VerticalOptions" Value="CenterAndExpand" />
         <Setter Property="BorderColor" Value="Lime" />
-        <Setter Property="BorderRadius" Value="5" />
-        <Setter Property="BorderWidth" Value="5" />
+        <Setter Property="BorderRadius" Value="15" />
+        <Setter Property="BorderWidth" Value="10" />
         <Setter Property="WidthRequest" Value="200" />
         <Setter Property="TextColor" Value="Teal" />
       </Style>
@@ -83,6 +87,8 @@
         <Setter Property="Padding" Value="5,5,5,5" />
         <Setter Property="BackgroundColor" Value="{StaticResource PageBackgroundColor}" />
       </Style>
+      
+      
     </ResourceDictionary>
   </Application.Resources>
 </Application>
\ No newline at end of file
diff --git a/BookAStar/BookAStar/Helpers/LocaLEntity.cs b/BookAStar/BookAStar/Helpers/LocaLEntity.cs
index 6ec0f775..3a24c71c 100644
--- a/BookAStar/BookAStar/Helpers/LocaLEntity.cs
+++ b/BookAStar/BookAStar/Helpers/LocaLEntity.cs
@@ -10,7 +10,9 @@ namespace BookAStar
     public class LocalEntity<V, K> : ObservableCollection<V>, ILocalEntity<V, K> where K : IEquatable<K>
     {
         public V CurrentItem { get; protected set; }
+
         public Func<V, K> GetKey { get; set; }
+
         public LocalEntity(Func<V, K> getKey) : base()
         {
             if (getKey == null) throw new InvalidOperationException();
@@ -28,6 +30,7 @@ namespace BookAStar
             Add(item);
             CurrentItem = item;
         }
+
         public V LocalGet(K key)
         {
             CurrentItem = this.Single(x => GetKey(x).Equals(key));
@@ -38,6 +41,11 @@ namespace BookAStar
         {
             this.Populate<V>();
         }
+
+        public void Load(string subKey)
+        {
+            this.Populate<V>(subKey);
+        }
     }
 
 }
\ No newline at end of file
diff --git a/BookAStar/BookAStar/Helpers/MainSettings.cs b/BookAStar/BookAStar/Helpers/MainSettings.cs
index 8da30074..2f8bbd75 100644
--- a/BookAStar/BookAStar/Helpers/MainSettings.cs
+++ b/BookAStar/BookAStar/Helpers/MainSettings.cs
@@ -33,7 +33,6 @@ namespace BookAStar
         #region Setting Constants
         public static readonly string SettingsDefault = string.Empty;
         public static readonly string EntityDataSettingsPrefix = "Ed";
-        public static readonly string EntityCursorSettingsPrefix = "Ec";
         private const string userNameKey = "user_id";
         private const string PushNotificationsKey = "pushNotifs";
         private const string AllowGPSUsageKey = "allowGPSUsage";
diff --git a/BookAStar/BookAStar/Interfaces/IEstimate.cs b/BookAStar/BookAStar/Interfaces/IEstimate.cs
index 9a1f92b3..662546cd 100644
--- a/BookAStar/BookAStar/Interfaces/IEstimate.cs
+++ b/BookAStar/BookAStar/Interfaces/IEstimate.cs
@@ -5,9 +5,9 @@ namespace BookAStar.Model.Interfaces
 {
     public interface IEstimate
     {
-        List<string> AttachedFiles { get; set; }
-        List<string> AttachedGraphics { get; }
-        List<BillingLine> Bill { get; set; }
+        IList<string> AttachedFiles { get; set; }
+        IList<string> AttachedGraphics { get; }
+        IList<BillingLine> Bill { get; set; }
         string ClientId { get; set; }
         long? CommandId { get; set; }
         string CommandType { get; set; }
diff --git a/BookAStar/BookAStar/Interfaces/ILocalEntity.cs b/BookAStar/BookAStar/Interfaces/ILocalEntity.cs
index 38988e9f..8e1f1945 100644
--- a/BookAStar/BookAStar/Interfaces/ILocalEntity.cs
+++ b/BookAStar/BookAStar/Interfaces/ILocalEntity.cs
@@ -7,6 +7,11 @@ namespace BookAStar
         void Load();
     }
 
+    public interface IPersistentOnDemand : ILoadable
+    {
+        void Save();
+    }
+
     public interface ILocalEntity<V, K> : ILoadable where K : IEquatable<K>
     {
         V CurrentItem { get; }
diff --git a/BookAStar/BookAStar/Model/Workflow/Estimate.cs b/BookAStar/BookAStar/Model/Workflow/Estimate.cs
index cce5645a..ba82c9a4 100644
--- a/BookAStar/BookAStar/Model/Workflow/Estimate.cs
+++ b/BookAStar/BookAStar/Model/Workflow/Estimate.cs
@@ -14,7 +14,7 @@ namespace BookAStar.Model.Workflow
         public string Description { get; set; }
         public int? Status { get; set; }
         public string Title { get; set; }
-        public List<BillingLine> Bill { get; set; }
+        public IList<BillingLine> Bill { get; set; }
         /// <summary>
         /// List of attached graphic files
         /// to this estimate, as relative pathes to
@@ -22,7 +22,7 @@ namespace BookAStar.Model.Workflow
         /// In db, they are separated by <c>:</c>
         /// </summary>
         /// <returns></returns>
-        public List<string> AttachedGraphics { get; set; }
+        public IList<string> AttachedGraphics { get; set; }
 
         public string AttachedGraphicsString
         {
@@ -36,7 +36,7 @@ namespace BookAStar.Model.Workflow
         /// In db, they are separated by <c>:</c>
         /// </summary>
         /// <returns></returns>
-        public List<string> AttachedFiles { get; set; }
+        public IList<string> AttachedFiles { get; set; }
         public string AttachedFilesString
         {
             get { return AttachedFiles == null ? null : string.Join(":", AttachedFiles); }
diff --git a/BookAStar/BookAStar/Pages/EditEstimatePage.xaml b/BookAStar/BookAStar/Pages/EditEstimatePage.xaml
index 78bbe098..88c9f693 100644
--- a/BookAStar/BookAStar/Pages/EditEstimatePage.xaml
+++ b/BookAStar/BookAStar/Pages/EditEstimatePage.xaml
@@ -37,8 +37,9 @@
                         ></views:MarkdownView>
     
     
-    <ListView x:Name="BillListView" ItemsSource="{Binding Bill}" >
-      <ListView.ItemTemplate RowHeight="20">
+    <ListView x:Name="BillListView" ItemsSource="{Binding Bill}" 
+           VerticalOptions="End" MinimumHeightRequest="30" >
+      <ListView.ItemTemplate>
                 <DataTemplate >
           <ViewCell>
             <ViewCell.View>
@@ -54,51 +55,20 @@
                 </Grid.ColumnDefinitions>
                 <Label Text="{Binding Description}"
                        Grid.Row="0" Grid.Column="0" ></Label>
-                <Label Text="{Binding Duration}"
+                <Label Text="{Binding Duration, StringFormat=\{0\}}"
                        Grid.Row="0" Grid.Column="1" ></Label>
                 <Label Text="{Binding Count}"
                        Grid.Row="0" Grid.Column="2" ></Label>
                 <Label Text="{Binding UnitaryCost}"
-                       Grid.Row="0" Grid.Column="3" ></Label>
+                       Grid.Row="0" Grid.Column="3"
+                       FontFamily="Monospace"></Label>
               </Grid> 
               </ViewCell.View>
           </ViewCell>
         </DataTemplate>
       </ListView.ItemTemplate>
     </ListView>
- <!-- 
-    <ListView x:Name="BillListView" View.VerticalOptions="End"
-      RelativeLayout.HeightConstraint="{ConstraintExpression Type=RelativeToParent, Property=Height Factor=.4}"
-      RelativeLayout.WidthConstraint="{ConstraintExpression Type=RelativeToParent, Property=Width, Factor=1}">
-      <ListView.ItemTemplate RowHeight="20">
-        <DataTemplate >
-          <ViewCell>
-            <ViewCell.View>
-            <Grid>
-                <Grid.RowDefinitions>
-                  <RowDefinition Height="*" />
-                </Grid.RowDefinitions>
-                <Grid.ColumnDefinitions>
-                  <ColumnDefinition Width="*" />
-                  <ColumnDefinition Width="*" />
-                  <ColumnDefinition Width="30" />
-                  <ColumnDefinition Width="90" />
-                </Grid.ColumnDefinitions>
-                <Label Text="{Binding Description}"
-                       Grid.Row="0" Grid.Column="0" ></Label>
-                <Label Text="{Binding Duration}"
-                       Grid.Row="0" Grid.Column="1" ></Label>
-                <Label Text="{Binding Count}"
-                       Grid.Row="0" Grid.Column="2" ></Label>
-                <Label Text="{Binding UnitaryCost}"
-                       Grid.Row="0" Grid.Column="3" ></Label>
-              </Grid> 
-              
-            </ViewCell.View>
-          </ViewCell>
-        </DataTemplate>
-      </ListView.ItemTemplate>
-    </ListView> -->
+ 
     <Button Text="Ajouter une ligne de facture" Clicked="OnNewCommanLine"></Button>
     <Label FormattedText="{Binding FormattedTotal}"/>
     <Button Text="Valider ce devis"></Button>
diff --git a/BookAStar/BookAStar/Pages/EditEstimatePage.xaml.cs b/BookAStar/BookAStar/Pages/EditEstimatePage.xaml.cs
index d8a397bf..6d5bfb10 100644
--- a/BookAStar/BookAStar/Pages/EditEstimatePage.xaml.cs
+++ b/BookAStar/BookAStar/Pages/EditEstimatePage.xaml.cs
@@ -25,6 +25,18 @@ namespace BookAStar.Pages
             BindingContext = model;
         }
 
+        protected override void OnBindingContextChanged()
+        {
+            base.OnBindingContextChanged();
+            ((EditEstimateViewModel)BindingContext).PropertyChanged += EditEstimatePage_PropertyChanged;
+
+        }
+
+        private void EditEstimatePage_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
+        {
+            
+        }
+
         protected void OnNewCommanLine(object sender, EventArgs e)
         {
             var com = new BillingLine() { Count = 1, UnitaryCost = 0.01m };
diff --git a/BookAStar/BookAStar/ViewModels/EditEstimateViewModel.cs b/BookAStar/BookAStar/ViewModels/EditEstimateViewModel.cs
index 94f88ea0..64961538 100644
--- a/BookAStar/BookAStar/ViewModels/EditEstimateViewModel.cs
+++ b/BookAStar/BookAStar/ViewModels/EditEstimateViewModel.cs
@@ -18,6 +18,13 @@ namespace BookAStar.ViewModels
             AttachedFiles = new ObservableCollection<string>(data.AttachedFiles);
             AttachedGraphicList = new ObservableCollection<string>(data.AttachedGraphics);
             Bill = new ObservableCollection<BillingLine>(data.Bill);
+            Bill.CollectionChanged += Bill_CollectionChanged;
+        }
+
+        private void Bill_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
+        {
+            Data.Bill = Bill;
+            NotifyPropertyChanged("FormattedTotal");
         }
 
         public Estimate Data { get; protected set; }