diff --git a/src/main/java/bg/softuni/invoice/model/base/UserBaseModel.java b/src/main/java/bg/softuni/invoice/model/base/UserBaseModel.java
new file mode 100644
index 0000000..2e932d8
--- /dev/null
+++ b/src/main/java/bg/softuni/invoice/model/base/UserBaseModel.java
@@ -0,0 +1,50 @@
+package bg.softuni.invoice.model.base;
+
+public abstract class UserBaseModel {
+
+    private String id;
+    private String username;
+    private String firstName;
+    private String lastName;
+    private boolean enabled;
+
+    public String getId() {
+        return id;
+    }
+
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public void setFirstName(String firstName) {
+        this.firstName = firstName;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+
+    public boolean isEnabled() {
+        return enabled;
+    }
+
+    public void setEnabled(boolean enabled) {
+        this.enabled = enabled;
+    }
+}
diff --git a/src/main/java/bg/softuni/invoice/model/service/UserServiceModel.java b/src/main/java/bg/softuni/invoice/model/service/UserServiceModel.java
index e3cfe7d..ef05794 100644
--- a/src/main/java/bg/softuni/invoice/model/service/UserServiceModel.java
+++ b/src/main/java/bg/softuni/invoice/model/service/UserServiceModel.java
@@ -1,53 +1,14 @@
 package bg.softuni.invoice.model.service;
 
+import bg.softuni.invoice.model.base.UserBaseModel;
+
 import java.util.HashSet;
 import java.util.Set;
 
-public class UserServiceModel {
+public class UserServiceModel extends UserBaseModel {
 
-    private String id;
-    private String username;
-    private String firstName;
-    private String lastName;
     private String password;
-    private Set<RoleServiceModel> authorities;
-    private boolean enabled;
-
-    public UserServiceModel() {
-        setAuthorities(new HashSet<>());
-    }
-
-    public String getId() {
-        return id;
-    }
-
-    public void setId(String id) {
-        this.id = id;
-    }
-
-    public String getUsername() {
-        return username;
-    }
-
-    public void setUsername(String username) {
-        this.username = username;
-    }
-
-    public String getFirstName() {
-        return firstName;
-    }
-
-    public void setFirstName(String firstName) {
-        this.firstName = firstName;
-    }
-
-    public String getLastName() {
-        return lastName;
-    }
-
-    public void setLastName(String lastName) {
-        this.lastName = lastName;
-    }
+    private Set<RoleServiceModel> authorities = new HashSet<>();
 
     public String getPassword() {
         return password;
@@ -64,12 +25,4 @@ public Set<RoleServiceModel> getAuthorities() {
     public void setAuthorities(Set<RoleServiceModel> authorities) {
         this.authorities = authorities;
     }
-
-    public boolean isEnabled() {
-        return enabled;
-    }
-
-    public void setEnabled(boolean enabled) {
-        this.enabled = enabled;
-    }
 }
diff --git a/src/main/java/bg/softuni/invoice/model/view/UserViewModel.java b/src/main/java/bg/softuni/invoice/model/view/UserViewModel.java
index c648568..e330762 100644
--- a/src/main/java/bg/softuni/invoice/model/view/UserViewModel.java
+++ b/src/main/java/bg/softuni/invoice/model/view/UserViewModel.java
@@ -1,47 +1,13 @@
 package bg.softuni.invoice.model.view;
 
-import java.util.Set;
-
-public class UserViewModel {
-
-    private String id;
-    private String username;
-    private String firstName;
-    private String lastName;
-    private Set<String> authorities;
-    private boolean enabled;
-
-    public String getId() {
-        return id;
-    }
-
-    public void setId(String id) {
-        this.id = id;
-    }
-
-    public String getUsername() {
-        return username;
-    }
-
-    public void setUsername(String username) {
-        this.username = username;
-    }
+import bg.softuni.invoice.model.base.UserBaseModel;
 
-    public String getFirstName() {
-        return firstName;
-    }
-
-    public void setFirstName(String firstName) {
-        this.firstName = firstName;
-    }
+import java.util.HashSet;
+import java.util.Set;
 
-    public String getLastName() {
-        return lastName;
-    }
+public class UserViewModel extends UserBaseModel {
 
-    public void setLastName(String lastName) {
-        this.lastName = lastName;
-    }
+    private Set<String> authorities = new HashSet<>();
 
     public Set<String> getAuthorities() {
         return authorities;
@@ -50,12 +16,4 @@ public Set<String> getAuthorities() {
     public void setAuthorities(Set<String> authorities) {
         this.authorities = authorities;
     }
-
-    public boolean isEnabled() {
-        return enabled;
-    }
-
-    public void setEnabled(boolean enabled) {
-        this.enabled = enabled;
-    }
 }
diff --git a/src/test/java/bg/softuni/invoice/model/view/UserViewModelTest.java b/src/test/java/bg/softuni/invoice/model/view/UserViewModelTest.java
index ada12cb..c9ea25b 100644
--- a/src/test/java/bg/softuni/invoice/model/view/UserViewModelTest.java
+++ b/src/test/java/bg/softuni/invoice/model/view/UserViewModelTest.java
@@ -7,6 +7,7 @@
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
@@ -152,12 +153,13 @@ void authorities_withValidValue_shouldReturnCorrectAuthorities() {
     }
 
     @Test
-    void authorities_whenNotSet_shouldReturnNull() {
+    void authorities_whenNotSet_shouldReturnEmptyCollection() {
         UserViewModel userViewModel = new UserViewModel();
 
         Set<String> actualAuthorities = userViewModel.getAuthorities();
 
-        assertNull(actualAuthorities);
+        assertNotNull(actualAuthorities);
+        assertTrue(actualAuthorities.isEmpty());
     }
 
     @Test