diff --git a/src/main/java/cz/cvut/fel/sit/omo/foodchain/node/base/NodeBase.java b/src/main/java/cz/cvut/fel/sit/omo/foodchain/node/base/NodeBase.java
index 8db8843..7b8988f 100644
--- a/src/main/java/cz/cvut/fel/sit/omo/foodchain/node/base/NodeBase.java
+++ b/src/main/java/cz/cvut/fel/sit/omo/foodchain/node/base/NodeBase.java
@@ -19,10 +19,10 @@ import java.util.*;
 
 
 public class NodeBase implements ChannelObserver {
-    private final Map<ChannelBase, ChannelSubscriptionType> subscribedChannels;
-    private final List<Product> products;
-    private final List<Transaction> refusedTransactions;
-    private final List<RefusedRequirement> refusedRequirements;
+    private final Map<ChannelBase, ChannelSubscriptionType> subscribedChannels = new HashMap<>();
+    private final List<Product> products = new LinkedList<>();
+    private final List<Transaction> refusedTransactions = new LinkedList<>();
+    private final List<RefusedRequirement> refusedRequirements = new LinkedList<>();
 
     private MonetaryAmount money;
 
@@ -32,18 +32,11 @@ public class NodeBase implements ChannelObserver {
 
     public NodeBase() {
         this.nodeType = NodeType.None;
-        this.subscribedChannels = new HashMap<>();
-        this.products = new LinkedList<>();
-        this.refusedTransactions = new LinkedList<>();
-        this.refusedRequirements = new LinkedList<>();
         this.money = Money.of(0, "USD");
     }
 
     public NodeBase(double m) {
-        this.subscribedChannels = new HashMap<>();
-        this.products = new LinkedList<>();
-        this.refusedTransactions = new LinkedList<>();
-        this.refusedRequirements = new LinkedList<>();
+        this.nodeType = NodeType.None;
         this.money = Money.of(m, "USD");
     }
 
@@ -271,18 +264,18 @@ public class NodeBase implements ChannelObserver {
         receiveTransactions();
         //System.out.println(this.getClass().getSimpleName() + ": " + money.getNumber());
     }
-}
 
-class RefusedRequirement {
-    public final TransactionType tType;
-    public final ProductType pType;
-    public final String pName;
-    public final MonetaryAmount price;
+    private static class RefusedRequirement {
+        public final TransactionType tType;
+        public final ProductType pType;
+        public final String pName;
+        public final MonetaryAmount price;
 
-    public RefusedRequirement(TransactionType tType, ProductType pType, String pName, MonetaryAmount price) {
-        this.tType = tType;
-        this.pType = pType;
-        this.pName = pName;
-        this.price = price;
+        public RefusedRequirement(TransactionType tType, ProductType pType, String pName, MonetaryAmount price) {
+            this.tType = tType;
+            this.pType = pType;
+            this.pName = pName;
+            this.price = price;
+        }
     }
 }