diff --git a/swap_meet/clothing.py b/swap_meet/clothing.py
index b8afdeb1e..a6de15a84 100644
--- a/swap_meet/clothing.py
+++ b/swap_meet/clothing.py
@@ -1,2 +1,9 @@
-class Clothing:
-    pass
\ No newline at end of file
+from .item import Item 
+
+class Clothing(Item):
+    def __init__(self, category = "Clothing", condition = 0, age = 0):
+        super().__init__(category, condition, age)
+        
+
+    def __str__(self):
+        return "The finest clothing you could wear."
\ No newline at end of file
diff --git a/swap_meet/decor.py b/swap_meet/decor.py
index eab7a9dbe..c2cded8c6 100644
--- a/swap_meet/decor.py
+++ b/swap_meet/decor.py
@@ -1,2 +1,9 @@
-class Decor:
-    pass
\ No newline at end of file
+from .item import Item 
+
+class Decor(Item):
+    def __init__(self, category = "Decor", condition = 0, age = 0):
+        super().__init__(category, condition, age)
+    
+
+    def __str__(self):
+        return "Something to decorate your space."
\ No newline at end of file
diff --git a/swap_meet/electronics.py b/swap_meet/electronics.py
index 2f9dff68a..fc5e3b645 100644
--- a/swap_meet/electronics.py
+++ b/swap_meet/electronics.py
@@ -1,2 +1,9 @@
-class Electronics:
-    pass
+from .item import Item 
+
+class Electronics(Item):
+    def __init__(self, category = "Electronics", condition = 0, age = 0):
+        super().__init__(category, condition, age)
+        
+
+    def __str__(self):
+        return "A gadget full of buttons and secrets."
diff --git a/swap_meet/item.py b/swap_meet/item.py
index 560d759c2..a44a85a8e 100644
--- a/swap_meet/item.py
+++ b/swap_meet/item.py
@@ -1,2 +1,31 @@
 class Item:
-    pass
\ No newline at end of file
+    def __init__(self, category = None, condition = 0, age = 0):
+        if not category:
+            category = ""
+        self.category = category
+        self.condition = condition
+        self.age = age
+        
+
+    def __str__(self):
+        return "Hello World!"
+
+
+    def age_statement(self):
+        return f"This item was made {self.age} months ago."
+    
+
+    def condition_description(self):
+        if self.condition == 0:
+            description = "horrendous quality"
+        elif self.condition == 1:
+            description = "terrible quality"
+        elif self.condition == 2:
+            description = "bad quality"
+        elif self.condition == 3:
+            description = "decent quality"
+        elif self.condition == 4:
+            description = "great quality"
+        elif self.condition == 5:
+            description = "exquisite quality"
+        return f"This item's condition is {description}"
\ No newline at end of file
diff --git a/swap_meet/vendor.py b/swap_meet/vendor.py
index 87302c056..985721282 100644
--- a/swap_meet/vendor.py
+++ b/swap_meet/vendor.py
@@ -1,2 +1,102 @@
 class Vendor:
-    pass
\ No newline at end of file
+    def __init__(self, inventory = None):
+        if not inventory:
+            inventory = []
+        self.inventory = inventory
+
+
+    def add(self, item):
+        self.inventory.append(item)
+        return item
+        
+
+    def remove(self, item):
+        if item in self.inventory:
+            self.inventory.remove(item)
+            return item
+        return False 
+
+
+    def get_by_category(self, category):
+        inventory_by_category = [] 
+        for item in self.inventory:
+            if item.category == category:
+                inventory_by_category.append(item)
+        return inventory_by_category
+            
+                
+    def swap_items(self, other_vendor, my_item, their_item):
+        if my_item in self.inventory and their_item in other_vendor.inventory:
+            other_vendor.add(my_item)
+            self.remove(my_item)
+            self.add(their_item)
+            other_vendor.remove(their_item)
+            return True 
+        return False 
+    
+
+    def swap_first_item(self, other_vendor):
+        try:
+            my_item = self.inventory[0]
+            their_item = other_vendor.inventory[0]
+            first_items = self.swap_items(other_vendor, my_item, their_item)
+            return first_items
+        except IndexError:
+            return False 
+
+
+    def get_best_by_category(self, category):
+        max_condition = 0
+        max_item = None 
+        for item in self.inventory:
+            if item.condition > max_condition and item.category == category:
+                max_condition = item.condition  
+                max_item = item
+        return max_item 
+
+
+    def swap_best_by_category(self, other, my_priority, their_priority):
+        my_item = other.get_best_by_category(my_priority)
+        their_item = self.get_best_by_category(their_priority)
+        return self.swap_items(other, their_item, my_item)
+
+
+
+############### Optional Enhancement for Wave 07 ###############
+    def get_newest_item(self):
+        newest_age = 1000
+        newest_item = None 
+        for item in self.inventory:
+            if item.age < newest_age: 
+                newest_age = item.age  
+                newest_item = item
+        return newest_item
+
+
+    def swap_by_newest(self, other, my_item, their_item):
+        their_item = self.get_newest_item()
+        my_item = other.get_newest_item()
+        return self.swap_items(other, their_item, my_item)
+
+        
+
+
+
+            
+            
+    
+        
+                
+        
+        
+        
+
+
+        
+
+
+
+        
+
+
+
diff --git a/tests/integration_tests/test_wave_01_02_03.py b/tests/integration_tests/test_wave_01_02_03.py
index 9912414da..9b2edbe81 100644
--- a/tests/integration_tests/test_wave_01_02_03.py
+++ b/tests/integration_tests/test_wave_01_02_03.py
@@ -2,8 +2,9 @@
 from swap_meet.vendor import Vendor
 from swap_meet.item import Item
 
-@pytest.mark.skip
-@pytest.mark.integration_test
+# Test 15
+#@pytest.mark.skip
+#@pytest.mark.integration_test
 def test_integration_wave_01_02_03():
     # make a vendor  
     vendor = Vendor()
diff --git a/tests/integration_tests/test_wave_04_05_06.py b/tests/integration_tests/test_wave_04_05_06.py
index 4d0be9909..bc3ea5f61 100644
--- a/tests/integration_tests/test_wave_04_05_06.py
+++ b/tests/integration_tests/test_wave_04_05_06.py
@@ -4,8 +4,9 @@
 from swap_meet.decor import Decor
 from swap_meet.electronics import Electronics
 
-@pytest.mark.skip
-@pytest.mark.integration_test
+# Test 33
+# @pytest.mark.skip
+# @pytest.mark.integration_test
 def test_integration_wave_04_05_06():
     camila = Vendor()
     valentina = Vendor()
diff --git a/tests/unit_tests/test_wave_01.py b/tests/unit_tests/test_wave_01.py
index 58478ccf9..4510ea05c 100644
--- a/tests/unit_tests/test_wave_01.py
+++ b/tests/unit_tests/test_wave_01.py
@@ -2,12 +2,14 @@
 import pytest
 from swap_meet.vendor import Vendor
 
-@pytest.mark.skip
+# Test 1
+#@pytest.mark.skip
 def test_vendor_has_inventory():
     vendor = Vendor()
     assert len(vendor.inventory) == 0
 
-@pytest.mark.skip
+# Test 2
+#@pytest.mark.skip
 def test_vendor_takes_optional_inventory():
     inventory = ["a", "b", "c"]
     vendor = Vendor(inventory=inventory)
@@ -16,18 +18,19 @@ def test_vendor_takes_optional_inventory():
     assert "b" in vendor.inventory
     assert "c" in vendor.inventory
 
-@pytest.mark.skip
+# Test 3
+#@pytest.mark.skip
 def test_adding_to_inventory():
     vendor = Vendor()
     item = "new item"
-
     result = vendor.add(item)
 
     assert len(vendor.inventory) == 1
     assert item in vendor.inventory
     assert result == item
 
-@pytest.mark.skip
+# Test 4
+#@pytest.mark.skip
 def test_removing_from_inventory_returns_item():
     item = "item to remove"
     vendor = Vendor(
@@ -39,8 +42,10 @@ def test_removing_from_inventory_returns_item():
     assert len(vendor.inventory) == 3
     assert item not in vendor.inventory
     assert result == item
+    
 
-@pytest.mark.skip
+# Test 5
+#@pytest.mark.skip
 def test_removing_not_found_is_false():
     item = "item to remove"
     vendor = Vendor(
@@ -49,7 +54,7 @@ def test_removing_not_found_is_false():
 
     result = vendor.remove(item)
 
-    raise Exception("Complete this test according to comments below.")
+    #raise Exception("Complete this test according to comments below.")
     # *********************************************************************
-    # ****** Complete Assert Portion of this test **********
+    assert result == False
     # *********************************************************************
diff --git a/tests/unit_tests/test_wave_02.py b/tests/unit_tests/test_wave_02.py
index 3d7060d7c..f59779166 100644
--- a/tests/unit_tests/test_wave_02.py
+++ b/tests/unit_tests/test_wave_02.py
@@ -2,12 +2,14 @@
 from swap_meet.vendor import Vendor
 from swap_meet.item import Item
 
-@pytest.mark.skip
+# Test 6
+#@pytest.mark.skip
 def test_items_have_blank_default_category():
     item = Item()
     assert item.category == ""
 
-@pytest.mark.skip
+# Test 7
+#@pytest.mark.skip
 def test_get_items_by_category():
     item_a = Item(category="clothing")
     item_b = Item(category="electronics")
@@ -23,7 +25,8 @@ def test_get_items_by_category():
     assert item_c in items
     assert item_b not in items
 
-@pytest.mark.skip
+# Test 8
+#@pytest.mark.skip
 def test_get_no_matching_items_by_category():
     item_a = Item(category="clothing")
     item_b = Item(category="clothing")
@@ -34,7 +37,8 @@ def test_get_no_matching_items_by_category():
 
     items = vendor.get_by_category("electronics")
 
-    raise Exception("Complete this test according to comments below.")
+    #raise Exception("Complete this test according to comments below.")
     # *********************************************************************
-    # ****** Complete Assert Portion of this test **********
+    assert items == []
+    assert len(items) == 0
     # *********************************************************************
diff --git a/tests/unit_tests/test_wave_03.py b/tests/unit_tests/test_wave_03.py
index 0300b638f..0cfd0eead 100644
--- a/tests/unit_tests/test_wave_03.py
+++ b/tests/unit_tests/test_wave_03.py
@@ -2,7 +2,8 @@
 from swap_meet.vendor import Vendor
 from swap_meet.item import Item
 
-@pytest.mark.skip
+# Test 9
+#@pytest.mark.skip
 def test_item_overrides_to_string():
     item = Item()
 
@@ -10,7 +11,8 @@ def test_item_overrides_to_string():
 
     assert stringified_item == "Hello World!"
 
-@pytest.mark.skip
+# Test 10
+#@pytest.mark.skip
 def test_swap_items_returns_true():
     item_a = Item(category="clothing")
     item_b = Item(category="clothing")
@@ -38,7 +40,8 @@ def test_swap_items_returns_true():
     assert item_b in jolie.inventory
     assert result
 
-@pytest.mark.skip
+# Test 11
+#@pytest.mark.skip
 def test_swap_items_when_my_item_is_missing_returns_false():
     item_a = Item(category="clothing")
     item_b = Item(category="clothing")
@@ -65,7 +68,8 @@ def test_swap_items_when_my_item_is_missing_returns_false():
     assert item_e in jolie.inventory
     assert not result
 
-@pytest.mark.skip
+# Test 12
+#@pytest.mark.skip
 def test_swap_items_when_their_item_is_missing_returns_false():
     item_a = Item(category="clothing")
     item_b = Item(category="clothing")
@@ -92,7 +96,8 @@ def test_swap_items_when_their_item_is_missing_returns_false():
     assert item_e in jolie.inventory
     assert not result
 
-@pytest.mark.skip
+# Test 13
+#@pytest.mark.skip
 def test_swap_items_from_my_empty_returns_false():
     fatimah = Vendor(
         inventory=[]
@@ -112,7 +117,8 @@ def test_swap_items_from_my_empty_returns_false():
     assert len(jolie.inventory) == 2
     assert not result
 
-@pytest.mark.skip
+# Test 14
+#@pytest.mark.skip
 def test_swap_items_from_their_empty_returns_false():
     item_a = Item(category="clothing")
     item_b = Item(category="clothing")
diff --git a/tests/unit_tests/test_wave_04.py b/tests/unit_tests/test_wave_04.py
index 8190a4ebb..7e28cb0b9 100644
--- a/tests/unit_tests/test_wave_04.py
+++ b/tests/unit_tests/test_wave_04.py
@@ -2,7 +2,8 @@
 from swap_meet.vendor import Vendor
 from swap_meet.item import Item
 
-@pytest.mark.skip
+# Test 16
+#@pytest.mark.skip
 def test_swap_first_item_returns_true():
     item_a = Item(category="clothing")
     item_b = Item(category="clothing")
@@ -30,7 +31,8 @@ def test_swap_first_item_returns_true():
     assert item_a in jolie.inventory
     assert result
 
-@pytest.mark.skip
+# Test 17
+#@pytest.mark.skip
 def test_swap_first_item_from_my_empty_returns_false():
     fatimah = Vendor(
         inventory=[]
@@ -48,7 +50,8 @@ def test_swap_first_item_from_my_empty_returns_false():
     assert len(jolie.inventory) == 2
     assert not result
 
-@pytest.mark.skip
+# Test 18
+#@pytest.mark.skip
 def test_swap_first_item_from_their_empty_returns_false():
     item_a = Item(category="clothing")
     item_b = Item(category="clothing")
diff --git a/tests/unit_tests/test_wave_05.py b/tests/unit_tests/test_wave_05.py
index 7abea06cd..d8dfec659 100644
--- a/tests/unit_tests/test_wave_05.py
+++ b/tests/unit_tests/test_wave_05.py
@@ -3,25 +3,29 @@
 from swap_meet.decor import Decor
 from swap_meet.electronics import Electronics
 
-@pytest.mark.skip
+# Test 19
+#@pytest.mark.skip
 def test_clothing_has_default_category_and_to_str():
     cloth = Clothing()
     assert cloth.category == "Clothing"
     assert str(cloth) == "The finest clothing you could wear."
 
-@pytest.mark.skip
+# Test 20
+#@pytest.mark.skip
 def test_decor_has_default_category_and_to_str():
     decor = Decor()
     assert decor.category == "Decor"
     assert str(decor) == "Something to decorate your space."
 
-@pytest.mark.skip
+# Test 21
+#@pytest.mark.skip
 def test_electronics_has_default_category_and_to_str():
     electronics = Electronics()
     assert electronics.category == "Electronics"
     assert str(electronics) == "A gadget full of buttons and secrets."
 
-@pytest.mark.skip
+# Test 22
+#@pytest.mark.skip
 def test_items_have_condition_as_float():
     items = [
         Clothing(condition=3.5),
@@ -31,7 +35,8 @@ def test_items_have_condition_as_float():
     for item in items:
         assert item.condition == pytest.approx(3.5)
 
-@pytest.mark.skip
+# Test 23
+#@pytest.mark.skip
 def test_items_have_condition_descriptions_that_are_the_same_regardless_of_type():
     items = [
         Clothing(condition=5),
@@ -52,3 +57,20 @@ def test_items_have_condition_descriptions_that_are_the_same_regardless_of_type(
         assert item.condition_description() == one_condition_description
 
     assert one_condition_description != five_condition_description
+
+
+                ####################################
+# Test 43(last)- Check for other condition values to obtain full code coverage
+#@pytest.mark.skip
+def test_condition_description_returns_correct_description_for_that_value():
+    items = [
+        Decor(condition=0),
+        Clothing(condition=1),
+        Electronics(condition=2),
+        Clothing(condition=3),
+        Decor(condition=4),
+        Electronics(condition=5)
+    ]
+    
+    for item in items:
+        assert item.condition_description()
diff --git a/tests/unit_tests/test_wave_06.py b/tests/unit_tests/test_wave_06.py
index 1f7065ab4..f98a027ee 100644
--- a/tests/unit_tests/test_wave_06.py
+++ b/tests/unit_tests/test_wave_06.py
@@ -4,7 +4,8 @@
 from swap_meet.decor import Decor
 from swap_meet.electronics import Electronics
 
-@pytest.mark.skip
+# Test 24
+#@pytest.mark.skip
 def test_best_by_category():
     item_a = Clothing(condition=2.0)
     item_b = Decor(condition=2.0)
@@ -20,7 +21,8 @@ def test_best_by_category():
     assert best_item.category == "Clothing"
     assert best_item.condition == pytest.approx(4.0)
 
-@pytest.mark.skip
+# Test 25
+#@pytest.mark.skip
 def test_best_by_category_no_matches_is_none():
     item_a = Decor(condition=2.0)
     item_b = Decor(condition=2.0)
@@ -33,7 +35,8 @@ def test_best_by_category_no_matches_is_none():
 
     assert best_item is None
 
-@pytest.mark.skip
+# Test 26
+#@pytest.mark.skip
 def test_best_by_category_with_duplicates():
     # Arrange
     item_a = Clothing(condition=2.0)
@@ -50,10 +53,10 @@ def test_best_by_category_with_duplicates():
     assert best_item.category == "Clothing"
     assert best_item.condition == pytest.approx(4.0)
 
-@pytest.mark.skip
+# Test 27
+#@pytest.mark.skip
 def test_swap_best_by_category():
     # Arrange
-    # me
     item_a = Decor(condition=2.0)
     item_b = Electronics(condition=4.0)
     item_c = Decor(condition=4.0)
@@ -61,7 +64,6 @@ def test_swap_best_by_category():
         inventory=[item_a, item_b, item_c]
     )
 
-    # them
     item_d = Clothing(condition=2.0)
     item_e = Decor(condition=4.0)
     item_f = Clothing(condition=4.0)
@@ -76,16 +78,27 @@ def test_swap_best_by_category():
         their_priority="Decor"
     )
 
-    raise Exception("Complete this test according to comments below.")
+    #raise Exception("Complete this test according to comments below.")
     # *********************************************************************
-    # ****** Complete Assert Portion of this test **********
+    assert result
+    assert len(tai.inventory) == 3
+    assert len(jesse.inventory) == 3
+    assert item_a in tai.inventory
+    assert item_b in tai.inventory
+    assert item_c not in tai.inventory
+    assert item_f in tai.inventory
+    assert item_d in jesse.inventory
+    assert item_e in jesse.inventory
+    assert item_f not in jesse.inventory
+    assert item_c in jesse.inventory
     # *********************************************************************
     # Assertions should check:
     # - That the results is truthy
     # - That tai and jesse's inventories are the correct length
     # - That all the correct items are in tai and jesse's inventories, including the items which were swapped from one vendor to the other
 
-@pytest.mark.skip
+# Test 28
+#@pytest.mark.skip
 def test_swap_best_by_category_reordered():
     # Arrange
     item_a = Decor(condition=2.0)
@@ -109,16 +122,27 @@ def test_swap_best_by_category_reordered():
         their_priority="Decor"
     )
 
-    raise Exception("Complete this test according to comments below.")
+    #raise Exception("Complete this test according to comments below.")
     # *********************************************************************
-    # ****** Complete Assert Portion of this test **********
+    assert result
+    assert len(tai.inventory) == 3
+    assert len(jesse.inventory) == 3
+    assert item_a in tai.inventory
+    assert item_b in tai.inventory
+    assert item_c not in tai.inventory
+    assert item_f in tai.inventory
+    assert item_d in jesse.inventory
+    assert item_e in jesse.inventory
+    assert item_f not in jesse.inventory
+    assert item_c in jesse.inventory
     # *********************************************************************
     # Assertions should check:
     # - That result is truthy
     # - That tai and jesse's inventories are the correct length
     # - That all the correct items are in tai and jesse's inventories, and that the items that were swapped are not there
 
-@pytest.mark.skip
+# Test 29
+#@pytest.mark.skip
 def test_swap_best_by_category_no_inventory_is_false():
     tai = Vendor(
         inventory=[]
@@ -144,7 +168,8 @@ def test_swap_best_by_category_no_inventory_is_false():
     assert item_b in jesse.inventory
     assert item_c in jesse.inventory
 
-@pytest.mark.skip
+# Test 30
+#@pytest.mark.skip
 def test_swap_best_by_category_no_other_inventory_is_false():
     item_a = Clothing(condition=2.0)
     item_b = Decor(condition=4.0)
@@ -170,7 +195,8 @@ def test_swap_best_by_category_no_other_inventory_is_false():
     assert item_b in tai.inventory
     assert item_c in tai.inventory
 
-@pytest.mark.skip
+# Test 31
+#@pytest.mark.skip
 def test_swap_best_by_category_no_match_is_false():
     # Arrange
     item_a = Decor(condition=2.0)
@@ -194,16 +220,25 @@ def test_swap_best_by_category_no_match_is_false():
         their_priority="Clothing"
     )
 
-    raise Exception("Complete this test according to comments below.")
+    #raise Exception("Complete this test according to comments below.")
     # *********************************************************************
-    # ****** Complete Assert Portion of this test **********
+    assert not result
+    assert len(tai.inventory) == 3
+    assert len(jesse.inventory) == 3
+    assert item_a in tai.inventory
+    assert item_b in tai.inventory
+    assert item_c in tai.inventory
+    assert item_d in jesse.inventory
+    assert item_e in jesse.inventory
+    assert item_f in jesse.inventory
     # *********************************************************************
     # Assertions should check:
     # - That result is falsy
     # - That tai and jesse's inventories are the correct length
     # - That all the correct items are in tai and jesse's inventories
 
-@pytest.mark.skip
+# Test 32
+#@pytest.mark.skip
 def test_swap_best_by_category_no_other_match_is_false():
     # Arrange
     item_a = Decor(condition=2.0)
@@ -227,9 +262,17 @@ def test_swap_best_by_category_no_other_match_is_false():
         their_priority="Decor"
     )
 
-    raise Exception("Complete this test according to comments below.")
+    #raise Exception("Complete this test according to comments below.")
     # *********************************************************************
-    # ****** Complete Assert Portion of this test **********
+    assert not result
+    assert len(tai.inventory) == 3
+    assert len(jesse.inventory) == 3
+    assert item_a in tai.inventory
+    assert item_b in tai.inventory
+    assert item_c in tai.inventory
+    assert item_d in jesse.inventory
+    assert item_e in jesse.inventory
+    assert item_f in jesse.inventory
     # *********************************************************************
     # Assertions should check:
     # - That result is falsy
diff --git a/tests/unit_tests/test_wave_07.py b/tests/unit_tests/test_wave_07.py
new file mode 100644
index 000000000..21aac296a
--- /dev/null
+++ b/tests/unit_tests/test_wave_07.py
@@ -0,0 +1,215 @@
+import pytest
+from swap_meet.vendor import Vendor
+from swap_meet.item import Item
+from swap_meet.clothing import Clothing
+from swap_meet.decor import Decor
+from swap_meet.electronics import Electronics
+
+# Test 34
+#@pytest.mark.skip
+def test_age_statement_by_default():
+    item = Item()
+    item_age = item.age_statement()
+
+    assert item.age == 0
+    assert item_age == "This item was made 0 months ago."
+
+
+# Test 35
+#@pytest.mark.skip
+def test_age_statement_with_different_value():
+    item = Item(age = 7)
+    item_age = item.age_statement()
+
+    assert item_age == "This item was made 7 months ago."
+
+
+# Test 36
+#@pytest.mark.skip
+def test_get_newest_item():
+    item_a = Clothing(age=1)
+    item_b = Decor(age=2)
+    item_c = Clothing(age=4)
+    item_d = Decor(age=5)
+    item_e = Clothing(age=3)
+    nishat = Vendor(
+        inventory=[item_a, item_b, item_c, item_d, item_e]
+    )
+
+    newest_item = nishat.get_newest_item()
+
+    assert newest_item
+    assert newest_item.category == "Clothing"
+    assert newest_item.age == pytest.approx(1)
+
+
+# Test 37
+#@pytest.mark.skip
+def test_newest_item_is_empty():
+    # item_a = Clothing(age=2)
+    # item_b = Decor(age=2)
+    # item_c = Clothing(age=4)
+    # item_d = Decor(age=5)
+    # item_e = Clothing(age=3)
+    nishat = Vendor(
+        inventory=[]
+    )
+
+    newest_item = nishat.get_newest_item()
+
+    assert newest_item is None
+
+
+# Test 38
+#@pytest.mark.skip
+def test_get_newest_item_with_duplicates_returns_first_item():
+    item_a = Clothing(age=2)
+    item_b = Decor(age=2)
+    item_c = Clothing(age=4)
+    item_d = Decor(age=5)
+    item_e = Clothing(age=3)
+    nishat = Vendor(
+        inventory=[item_a, item_b, item_c, item_d, item_e]
+    )
+
+    newest_item = nishat.get_newest_item()
+
+    
+    assert newest_item.age == 2
+    assert newest_item == item_a
+    
+
+# Test 39
+#@pytest.mark.skip
+def test_swap_newest_item():
+    # Arrange
+    item_a = Decor(age=12)
+    item_b = Electronics(age=8)
+    item_c = Decor(age=9)
+    nishat = Vendor(
+        inventory=[item_a, item_b, item_c]
+    )
+
+    item_d = Clothing(age=4)
+    item_e = Decor(age=7)
+    item_f = Clothing(age=14)
+    fatima = Vendor(
+        inventory=[item_d, item_e, item_f]
+    )
+
+    # Act
+    result = nishat.swap_by_newest(
+        other = fatima,
+        my_item = fatima.get_newest_item(),
+        their_item = nishat.get_newest_item()
+    )
+
+    assert result
+    assert len(nishat.inventory) == 3
+    assert len(fatima.inventory) == 3
+    assert item_a in nishat.inventory
+    assert item_b not in nishat.inventory
+    assert item_b in fatima.inventory
+    assert item_c in nishat.inventory
+    assert item_d not in fatima.inventory
+    assert item_d in nishat.inventory
+    assert item_e in fatima.inventory
+    assert item_f in fatima.inventory
+
+
+# Test 40
+#@pytest.mark.skip
+def test_swap_newest_item_reordered():
+    # Arrange
+    item_a = Decor(age=12)
+    item_b = Electronics(age=8)
+    item_c = Decor(age=9)
+    nishat = Vendor(
+        inventory=[item_c, item_b, item_a]
+    )
+
+    item_d = Clothing(age=4)
+    item_e = Decor(age=7)
+    item_f = Clothing(age=14)
+    fatima = Vendor(
+        inventory=[item_e, item_d, item_f]
+    )
+
+    # Act
+    result = nishat.swap_by_newest(
+        other = fatima,
+        my_item = fatima.get_newest_item(),
+        their_item = nishat.get_newest_item()
+    )
+
+    assert result
+    assert len(nishat.inventory) == 3
+    assert len(fatima.inventory) == 3
+    assert item_a in nishat.inventory
+    assert item_b not in nishat.inventory
+    assert item_b in fatima.inventory
+    assert item_c in nishat.inventory
+    assert item_d not in fatima.inventory
+    assert item_d in nishat.inventory
+    assert item_e in fatima.inventory
+    assert item_f in fatima.inventory
+    
+
+# Test 41
+#@pytest.mark.skip
+def test_swap_newest_item_self_inventory_empty():
+    # Arrange
+    nishat = Vendor(
+        inventory=[]
+    )
+
+    item_d = Clothing(age=4)
+    item_e = Decor(age=7)
+    item_f = Clothing(age=14)
+    fatima = Vendor(
+        inventory=[item_d, item_e, item_f]
+    )
+
+    # Act
+    result = nishat.swap_by_newest(
+        other = fatima,
+        my_item = fatima.get_newest_item(),
+        their_item = nishat.get_newest_item()
+    )
+
+    assert not result
+    assert len(nishat.inventory) == 0
+    assert len(fatima.inventory) == 3
+    assert item_d in fatima.inventory
+    assert item_e in fatima.inventory
+    assert item_f in fatima.inventory
+    
+
+# Test 42
+#@pytest.mark.skip
+def test_swap_newest_item_other_inventory_empty():
+    # Arrange
+    item_a = Decor(age=12)
+    item_b = Electronics(age=8)
+    item_c = Decor(age=9)
+    nishat = Vendor(
+        inventory=[item_a, item_b, item_c]
+    )
+
+    fatima = Vendor(
+        inventory=[]
+    )
+
+    # Act
+    result = nishat.swap_by_newest(
+        other = fatima,
+        my_item = fatima.get_newest_item(),
+        their_item = nishat.get_newest_item()
+    )
+
+    assert not result
+    assert len(nishat.inventory) == 3
+    assert len(fatima.inventory) == 0
+    assert item_a in nishat.inventory
+    assert item_b in nishat.inventory
+    assert item_c in nishat.inventory
\ No newline at end of file