diff --git a/src/test/java/com/h2/Module04_Test.java b/src/test/java/com/h2/Module04_Test.java
index 0ad1deefc..61e0181b6 100644
--- a/src/test/java/com/h2/Module04_Test.java
+++ b/src/test/java/com/h2/Module04_Test.java
@@ -17,7 +17,7 @@
 import static org.junit.platform.commons.util.ReflectionUtils.*;
 
 public class Module04_Test {
-    private final String classToFind = "com.h2.MortgageCalculator";
+    private static final String classToFind = "com.h2.MortgageCalculator";
     private final InputStream systemIn = System.in;
     private final PrintStream systemOut = System.out;
 
@@ -50,7 +50,7 @@ private static Optional<Class<?>> getClass(final String className) {
         return aClass.toOptional();
     }
 
-    public Optional<Class<?>> getMortgageClass() {
+    public static Optional<Class<?>> getMortgageClass() {
         return getClass(classToFind);
     }
 
diff --git a/src/test/java/com/h2/Module06_Test.java b/src/test/java/com/h2/Module06_Test.java
index e02f67516..7dfc08883 100644
--- a/src/test/java/com/h2/Module06_Test.java
+++ b/src/test/java/com/h2/Module06_Test.java
@@ -5,7 +5,10 @@
 
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
+import java.util.Arrays;
+import java.util.List;
 import java.util.Optional;
+import java.util.stream.Collectors;
 
 import static org.junit.jupiter.api.Assertions.*;
 import static org.junit.platform.commons.util.ReflectionUtils.*;
@@ -131,4 +134,43 @@ public void m6_05_testGetFloatValueExistenceAndCorrectness() throws IllegalAcces
             fail("Can't find a method with name " + methodName + " in class " + classToFind + " with 1 parameter of type 'String'");
         }
     }
+
+    @Test
+    public void m6_06_testMainMethodPrintsCorrectMortgageAmount() throws NoSuchMethodException {
+        final String methodName = "main";
+
+        final Optional<Class<?>> maybeMortgageCalculator = Module04_Test.getMortgageClass();
+        assertTrue(maybeMortgageCalculator.isPresent(), classToFind + " must exist");
+        final Class<?> mortgageCalculator = maybeMortgageCalculator.get();
+
+        final Method[] methods = mortgageCalculator.getDeclaredMethods();
+
+        final List<Method> filteredMethod = Arrays.stream(methods).filter(method -> method.getName().equals(methodName)).collect(Collectors.toList());
+        assertEquals(1, filteredMethod.size(), classToFind + " should contain a method called '" + methodName + "'");
+
+        final String loanAmount = "264000";
+        final String termInYears = "30";
+        final String annualRate = "3.74";
+        String input = "hello";
+
+        Method method = mortgageCalculator.getMethod("main", String[].class);
+        {
+            final InvocationTargetException exception = assertThrows(InvocationTargetException.class, () -> method.invoke(null, (Object) new String[]{input, termInYears, annualRate}));
+            Throwable targetException = exception.getTargetException();
+            assertEquals(IllegalArgumentException.class, targetException.getClass(), methodName + " should have thrown an instance of 'IllegalArgumentException'");
+            assertEquals(input + " cannot be converted into a 'long' value. Exiting program.", targetException.getMessage());
+        }
+        {
+            final InvocationTargetException exception = assertThrows(InvocationTargetException.class, () -> method.invoke(null, (Object) new String[]{loanAmount, input, annualRate}));
+            Throwable targetException = exception.getTargetException();
+            assertEquals(IllegalArgumentException.class, targetException.getClass(), methodName + " should have thrown an instance of 'IllegalArgumentException'");
+            assertEquals(input + " cannot be converted into a 'int' value. Exiting program.", targetException.getMessage());
+        }
+        {
+            final InvocationTargetException exception = assertThrows(InvocationTargetException.class, () -> method.invoke(null, (Object) new String[]{loanAmount, termInYears, input}));
+            Throwable targetException = exception.getTargetException();
+            assertEquals(IllegalArgumentException.class, targetException.getClass(), methodName + " should have thrown an instance of 'IllegalArgumentException'");
+            assertEquals(input + " cannot be converted into a 'float' value. Exiting program.", targetException.getMessage());
+        }
+    }
 }