diff --git a/spring_online_calculator/src/main/java/labWork/premium_store/model/Client.java b/spring_online_calculator/src/main/java/labWork/premium_store/model/Client.java
index 88b3f07..de82941 100644
--- a/spring_online_calculator/src/main/java/labWork/premium_store/model/Client.java
+++ b/spring_online_calculator/src/main/java/labWork/premium_store/model/Client.java
@@ -54,6 +54,14 @@ public class Client {
         this.balance = balance;
     }
 
+    public List<Tank> getTanks(){
+        return tanks;
+    }
+
+    public void setTanks(List<Tank> tanks){
+        this.tanks = tanks;
+    }
+
     //метод для сравнения
     @Override
     public boolean equals(Object o) {
@@ -81,6 +89,7 @@ public class Client {
                 ", nickName='" + nickName + '\'' +
                 ", email='" + email + '\'' +
                 ", balance='" + balance + '\'' +
+                ", tanks count='" + tanks.size() + '\'' +
                 '}';
     }
 }
diff --git a/spring_online_calculator/src/main/java/labWork/premium_store/model/Tank.java b/spring_online_calculator/src/main/java/labWork/premium_store/model/Tank.java
index f3b2ae1..f223c6f 100644
--- a/spring_online_calculator/src/main/java/labWork/premium_store/model/Tank.java
+++ b/spring_online_calculator/src/main/java/labWork/premium_store/model/Tank.java
@@ -35,15 +35,15 @@ public class Tank {
     public Tank() {
     }
 
-    public Long getId(){
-        return id;
-    }
-
     public Tank(String name, int cost) {
         this.name = name;
         this.cost = cost;
     }
 
+    public Long getId(){
+        return id;
+    }
+
     public String getName() {
         return name;
     }
@@ -111,6 +111,18 @@ public class Tank {
 
     @Override
     public int hashCode() {
-        return Objects.hash(getId(), getName(), getLevel(), getClients(), getCost());
+        return Objects.hash(id);
+    }
+
+    //преобразование данных по объекту в строчку
+    @Override
+    public String toString() {
+        return "Student{" +
+                "id=" + id +
+                ", name='" + name + '\'' +
+                ", nation='" + nation + '\'' +
+                ", level='" + level + '\'' +
+                ", cost='" + cost + '\'' +
+                '}';
     }
 }
diff --git a/spring_online_calculator/src/main/java/labWork/premium_store/service/ClientService.java b/spring_online_calculator/src/main/java/labWork/premium_store/service/ClientService.java
new file mode 100644
index 0000000..87a7994
--- /dev/null
+++ b/spring_online_calculator/src/main/java/labWork/premium_store/service/ClientService.java
@@ -0,0 +1,76 @@
+package labWork.premium_store.service;
+
+import labWork.premium_store.model.Client;
+import labWork.premium_store.model.Tank;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+import org.springframework.util.StringUtils;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityNotFoundException;
+import javax.persistence.PersistenceContext;
+import java.util.List;
+
+@Service
+public class ClientService {
+    @PersistenceContext
+    private EntityManager em;
+
+    @Transactional
+    public Client addClient(String newNickName, String newEmail, Integer newBallance) {
+        if (!StringUtils.hasText(newNickName) || !StringUtils.hasText(newEmail)) {
+            throw new IllegalArgumentException("NickName or newEmail is zero or empty");
+        }
+
+        final Client client = new Client(newNickName, newEmail, newBallance);
+        em.persist(client);
+
+        return client;
+    }
+
+    @Transactional(readOnly = true)
+    public Client findClient(Long id) {
+        final Client Client = em.find(Client.class, id);
+
+        if (Client == null) {
+            throw new EntityNotFoundException(String.format("Client with id [%s] is not found", id));
+        }
+
+        return Client;
+    }
+
+    @Transactional(readOnly = true)
+    public List<Client> findAllClients() {
+        return em.createQuery("select c from Client c", Client.class)
+                .getResultList();
+    }
+
+    @Transactional
+    public Client updateClient(Long id, String newNickName, String newEmail, Integer newBallance, List<Tank> newTanks) {
+        if (!StringUtils.hasText(newNickName) || !StringUtils.hasText(newEmail)) {
+            throw new IllegalArgumentException("NickName or newEmail is zero or empty");
+        }
+
+        final Client currentClient = findClient(id);
+
+        currentClient.setNickName(newNickName);
+        currentClient.setNickName(newNickName);
+        currentClient.setBalance(newBallance);
+        currentClient.setTanks(newTanks);
+
+        return em.merge(currentClient);
+    }
+
+    @Transactional
+    public Client deleteClient(Long id) {
+        final Client currentClient = findClient(id);
+        em.remove(currentClient);
+
+        return currentClient;
+    }
+
+    @Transactional
+    public void deleteAllClients() {
+        em.createQuery("Delete from Client").executeUpdate();
+    }
+}
diff --git a/spring_online_calculator/src/main/java/labWork/premium_store/service/LevelService.java b/spring_online_calculator/src/main/java/labWork/premium_store/service/LevelService.java
new file mode 100644
index 0000000..c90b13f
--- /dev/null
+++ b/spring_online_calculator/src/main/java/labWork/premium_store/service/LevelService.java
@@ -0,0 +1,67 @@
+package labWork.premium_store.service;
+
+import labWork.premium_store.model.Level;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+import org.springframework.util.StringUtils;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityNotFoundException;
+import javax.persistence.PersistenceContext;
+import java.util.List;
+
+@Service
+public class LevelService {
+    @PersistenceContext
+    private EntityManager em;
+
+    @Transactional
+    public Level addLevel(int newLevel) {
+        if (newLevel <= 0) {
+            throw new IllegalArgumentException("Level name is zero or less");
+        }
+        final Level level = new Level(newLevel);
+        em.persist(level);
+        return level;
+    }
+
+    @Transactional(readOnly = true)
+    public Level findLevel(Long id) {
+        final Level level = em.find(Level.class, id);
+        if (level == null) {
+            throw new EntityNotFoundException(String.format("Level with id [%s] is not found", id));
+        }
+        return level;
+    }
+
+    @Transactional(readOnly = true)
+    public List<Level> findAllLevels() {
+        return em.createQuery("select s from Level s", Level.class)
+                .getResultList();
+    }
+
+    @Transactional
+    public Level updateLevel(Long id, int newLevel) {
+        if (newLevel <= 0) {
+            throw new IllegalArgumentException("Level name is zero or less");
+        }
+
+        final Level currentLevel = findLevel(id);
+        currentLevel.setLevel(newLevel);
+
+        return em.merge(currentLevel);
+    }
+
+    @Transactional
+    public Level deleteLevel(Long id) {
+        final Level currentLevel = findLevel(id);
+        em.remove(currentLevel);
+
+        return currentLevel;
+    }
+
+    @Transactional
+    public void deleteAllLevels() {
+        em.createQuery("Delete from Level").executeUpdate();
+    }
+}
diff --git a/spring_online_calculator/src/main/java/labWork/premium_store/service/NationService.java b/spring_online_calculator/src/main/java/labWork/premium_store/service/NationService.java
new file mode 100644
index 0000000..263e783
--- /dev/null
+++ b/spring_online_calculator/src/main/java/labWork/premium_store/service/NationService.java
@@ -0,0 +1,71 @@
+package labWork.premium_store.service;
+
+import labWork.premium_store.model.Nation;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+import org.springframework.util.StringUtils;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityNotFoundException;
+import javax.persistence.PersistenceContext;
+import java.util.List;
+
+@Service
+public class NationService {
+    @PersistenceContext
+    private EntityManager em;
+
+    @Transactional
+    public Nation addNation(String nameNation){
+        if(!StringUtils.hasText(nameNation)){
+            throw new IllegalArgumentException("The name of the nation is null or empty");
+        }
+        
+        final Nation nation = new Nation(nameNation);
+        em.persist(nation);
+        
+        return nation;
+    }
+
+    @Transactional(readOnly = true)
+    public Nation findNation(Long id){
+        final Nation nation = em.find(Nation.class, id);
+
+        if(nation == null){
+            throw new EntityNotFoundException(String.format("Nation with id [%s] is not found", id));
+        }
+
+        return nation;
+    }
+
+    @Transactional(readOnly = true)
+    public List<Nation> findAllNations() {
+        return em.createQuery("select n from Nation n", Nation.class)
+                .getResultList();
+    }
+
+    @Transactional
+    public Nation updateNation(Long id, String newNation) {
+        if (!StringUtils.hasText(newNation)) {
+            throw new IllegalArgumentException("Student name is null or empty");
+        }
+
+        final Nation currentNation = findNation(id);
+        currentNation.setNation(newNation);
+
+        return em.merge(currentNation);
+    }
+
+    @Transactional
+    public Nation deleteNAtion(Long id) {
+        final Nation currentNation = findNation(id);
+        em.remove(currentNation);
+
+        return currentNation;
+    }
+
+    @Transactional
+    public void deleteAllNations() {
+        em.createQuery("delete from Nation").executeUpdate();
+    }
+}