diff --git a/Docs/pages/setup/01-properties.md b/Docs/pages/setup/01-properties.md
index e287a0d7..9b0bc47f 100644
--- a/Docs/pages/setup/01-properties.md
+++ b/Docs/pages/setup/01-properties.md
@@ -13,7 +13,7 @@ sut.SetupMock.Property.TotalDispensed.InitializeWith(42);
 
 **Returns / Throws**
 
-Alternatively, set up properties with `Returns` and `Throws` (supports sequences):
+Set up properties with `Returns` and `Throws` (supports sequences):
 
 ```csharp
 sut.SetupMock.Property.TotalDispensed
@@ -23,6 +23,13 @@ sut.SetupMock.Property.TotalDispensed
     .Returns(4);
 ```
 
+You can also return a value based on the previous value:
+
+```csharp
+sut.SetupMock.Property.TotalDispensed
+    .Returns((current) => current + 10);  // Increment by 10 each read
+```
+
 **Callbacks**
 
 Register callbacks on the setter or getter:
@@ -31,3 +38,29 @@ Register callbacks on the setter or getter:
 sut.SetupMock.Property.TotalDispensed.OnGet.Do(() => Console.WriteLine("TotalDispensed was read!"));
 sut.SetupMock.Property.TotalDispensed.OnSet.Do((oldValue, newValue) => Console.WriteLine($"Changed from {oldValue} to {newValue}!") );
 ```
+
+Callbacks can also receive the invocation counter and current value:
+
+```csharp
+// Getter with counter and current value
+sut.SetupMock.Property.TotalDispensed
+    .OnGet.Do((int count, int value) => 
+        Console.WriteLine($"Read #{count}, current value: {value}"));
+
+// Setter with counter and new value
+sut.SetupMock.Property.TotalDispensed
+    .OnSet.Do((int count, int newValue) => 
+        Console.WriteLine($"Set #{count} to {newValue}"));
+```
+
+**Register**
+
+Register a setup without providing a value (useful with `ThrowWhenNotSetup`):
+
+```csharp
+var strictMock = Mock.Create<IChocolateDispenser>(
+    new MockBehavior { ThrowWhenNotSetup = true });
+
+// Register property without value - won't throw
+strictMock.SetupMock.Property.TotalDispensed.Register();
+```
diff --git a/Docs/pages/setup/03-indexers.md b/Docs/pages/setup/03-indexers.md
index 8fe95e5a..6ccad3a9 100644
--- a/Docs/pages/setup/03-indexers.md
+++ b/Docs/pages/setup/03-indexers.md
@@ -14,8 +14,24 @@ sut.SetupMock.Indexer(It.Is("Dark"))
 
 - `.InitializeWith(…)` can take a value or a callback with parameters.
 - `.Returns(…)` and `.Throws(…)` support direct values, callbacks, and callbacks with parameters and/or the current
-  value.
-- `.OnGet.Do(…)` and `.OnSet.Do(…)` support callbacks with or without parameters.
+  value. You can also return a value based on the previous value:
+  ```csharp
+  sut.SetupMock.Indexer(It.Is("Dark"))
+      .Returns((string type, int current) => current + 10);  // Increment by 10 each read
+  ```
+- `.OnGet.Do(…)` and `.OnSet.Do(…)` support callbacks with or without parameters. Callbacks can receive the invocation
+  counter, indexer parameters, and current value:
+  ```csharp
+  // Getter with counter, parameter, and current value
+  sut.SetupMock.Indexer(It.IsAny<string>())
+      .OnGet.Do((int count, string type, int value) => 
+          Console.WriteLine($"Read #{count} for {type}, current value: {value}"));
+  
+  // Setter with counter, parameter, and new value
+  sut.SetupMock.Indexer(It.IsAny<string>())
+      .OnSet.Do((int count, string type, int newValue) => 
+          Console.WriteLine($"Set #{count} for {type} to {newValue}"));
+  ```
 - `.Returns(…)` and `.Throws(…)` can be chained to define a sequence of behaviors, which are cycled through on each
   call.
 - Use `.SkippingBaseClass(…)` to override the base class behavior for a specific indexer (only for class mocks).
diff --git a/README.md b/README.md
index 38611181..6bd56bca 100644
--- a/README.md
+++ b/README.md
@@ -193,7 +193,7 @@ sut.SetupMock.Property.TotalDispensed.InitializeWith(42);
 
 **Returns / Throws**
 
-Alternatively, set up properties with `Returns` and `Throws` (supports sequences):
+Set up properties with `Returns` and `Throws` (supports sequences):
 
 ```csharp
 sut.SetupMock.Property.TotalDispensed
@@ -203,6 +203,13 @@ sut.SetupMock.Property.TotalDispensed
     .Returns(4);
 ```
 
+You can also return a value based on the previous value:
+
+```csharp
+sut.SetupMock.Property.TotalDispensed
+    .Returns((current) => current + 10);  // Increment by 10 each read
+```
+
 **Callbacks**
 
 Register callbacks on the setter or getter:
@@ -212,6 +219,32 @@ sut.SetupMock.Property.TotalDispensed.OnGet.Do(() => Console.WriteLine("TotalDis
 sut.SetupMock.Property.TotalDispensed.OnSet.Do((oldValue, newValue) => Console.WriteLine($"Changed from {oldValue} to {newValue}!") );
 ```
 
+Callbacks can also receive the invocation counter and current value:
+
+```csharp
+// Getter with counter and current value
+sut.SetupMock.Property.TotalDispensed
+    .OnGet.Do((int count, int value) => 
+        Console.WriteLine($"Read #{count}, current value: {value}"));
+
+// Setter with counter and new value
+sut.SetupMock.Property.TotalDispensed
+    .OnSet.Do((int count, int newValue) => 
+        Console.WriteLine($"Set #{count} to {newValue}"));
+```
+
+**Register**
+
+Register a setup without providing a value (useful with `ThrowWhenNotSetup`):
+
+```csharp
+var strictMock = Mock.Create<IChocolateDispenser>(
+    new MockBehavior { ThrowWhenNotSetup = true });
+
+// Register property without value - won't throw
+strictMock.SetupMock.Property.TotalDispensed.Register();
+```
+
 ### Methods
 
 Use `mock.SetupMock.Method.MethodName(…)` to set up methods. You can specify argument matchers for each parameter.
@@ -275,8 +308,24 @@ sut.SetupMock.Indexer(It.Is("Dark"))
 
 - `.InitializeWith(…)` can take a value or a callback with parameters.
 - `.Returns(…)` and `.Throws(…)` support direct values, callbacks, and callbacks with parameters and/or the current
-  value.
-- `.OnGet.Do(…)` and `.OnSet.Do(…)` support callbacks with or without parameters.
+  value. You can also return a value based on the previous value:
+  ```csharp
+  sut.SetupMock.Indexer(It.Is("Dark"))
+      .Returns((string type, int current) => current + 10);  // Increment by 10 each read
+  ```
+- `.OnGet.Do(…)` and `.OnSet.Do(…)` support callbacks with or without parameters. Callbacks can receive the invocation
+  counter, indexer parameters, and current value:
+  ```csharp
+  // Getter with counter, parameter, and current value
+  sut.SetupMock.Indexer(It.IsAny<string>())
+      .OnGet.Do((int count, string type, int value) => 
+          Console.WriteLine($"Read #{count} for {type}, current value: {value}"));
+  
+  // Setter with counter, parameter, and new value
+  sut.SetupMock.Indexer(It.IsAny<string>())
+      .OnSet.Do((int count, string type, int newValue) => 
+          Console.WriteLine($"Set #{count} for {type} to {newValue}"));
+  ```
 - `.Returns(…)` and `.Throws(…)` can be chained to define a sequence of behaviors, which are cycled through on each
   call.
 - Use `.SkippingBaseClass(…)` to override the base class behavior for a specific indexer (only for class mocks).