--- a/tests/src/createItem.test.ts
+++ b/tests/src/createItem.test.ts
@@ -1,65 +1,57 @@
-import { stringToU8a, u8aToString } from '@polkadot/util';
-import { assert, expect } from 'chai';
+import { assert } from 'chai';
 import { alicesPublicKey } from './accounts';
 import privateKey from './substrate/privateKey';
-import usingApi from './substrate/substrate-api';
+import { default as usingApi } from './substrate/substrate-api';
 import waitNewBlocks from './substrate/wait-new-blocks';
-
-async function createCollection(name, desk, pref, mode) {
-  await usingApi(async (api) => {
-    const alicePrivateKey = privateKey('//Alice');
-    const AcollectionCount = await api.query.nft.collectionCount();
-    try {await api.tx.nft
-          .createCollection(name, desk, pref, mode)
-          .signAndSend(alicePrivateKey);
-         await waitNewBlocks(api);
-         const BcollectionCount = await api.query.nft.collectionCount();
-    // tslint:disable-next-line: max-line-length
-         if (BcollectionCount === AcollectionCount) {assert.fail('Error: collection NOT created.'); }} catch { assert.fail('Create collection error.'); }
-  });
-}
+import { createCollectionExpectSuccess } from './util/helpers';
 
 describe('integration test: ext. createItem():', () => {
   it('Create new item in NFT collection', async () => {
     await usingApi(async (api) => {
-      createCollection('1', '1', '0', 'NFT');
+      const createMode = 'NFT';
+      const alicePrivateKey = privateKey('//Alice');
+      await createCollectionExpectSuccess('0', '0', '0', createMode);
+      await waitNewBlocks(api);
       const newCollectionID = await api.query.nft.createdCollectionCount();
-      const alicePrivateKey = privateKey('//Alice');
       const AnftItemList = await api.query.nft.itemListIndex(newCollectionID);
       await api.tx.nft
-            .createItem(newCollectionID, alicesPublicKey, 'NFT')
+            .createItem(newCollectionID, alicesPublicKey, createMode)
             .signAndSend(alicePrivateKey);
       await waitNewBlocks(api);
       const BnftItemList = await api.query.nft.itemListIndex(newCollectionID);
-      if (BnftItemList === AnftItemList) {assert.fail('Error: new item in NFT collection NOT created.'); }
+      if (BnftItemList === AnftItemList) {assert.fail(`Error: new item in ${createMode} collection NOT created.`); }
     });
   });
   it('Create new item in Fungible collection', async () => {
     await usingApi(async (api) => {
-      createCollection('1', '1', '0', 'Fungible');
+      const createMode = 'Fungible';
+      const alicePrivateKey = privateKey('//Alice');
+      await createCollectionExpectSuccess('0', '0', '0', createMode);
+      await waitNewBlocks(api);
       const newCollectionID = await api.query.nft.createdCollectionCount();
-      const alicePrivateKey = privateKey('//Alice');
       const AnftItemList = await api.query.nft.itemListIndex(newCollectionID);
       await api.tx.nft
-            .createItem(newCollectionID, alicesPublicKey, 'Fungible')
+            .createItem(newCollectionID, alicesPublicKey, createMode)
             .signAndSend(alicePrivateKey);
       await waitNewBlocks(api);
       const BnftItemList = await api.query.nft.itemListIndex(newCollectionID);
-      if (BnftItemList === AnftItemList) {assert.fail('Error: new item in Fungible collection NOT created.'); }
+      if (BnftItemList === AnftItemList) {assert.fail(`Error: new item in ${createMode} collection NOT created.`); }
     });
   });
   it('Create new item in ReFungible collection', async () => {
     await usingApi(async (api) => {
-      createCollection('1', '1', '0', 'ReFungible');
+      const createMode = 'ReFungible';
+      const alicePrivateKey = privateKey('//Alice');
+      await createCollectionExpectSuccess('0', '0', '0', createMode);
+      await waitNewBlocks(api);
       const newCollectionID = await api.query.nft.createdCollectionCount();
-      const alicePrivateKey = privateKey('//Alice');
       const AnftItemList = await api.query.nft.itemListIndex(newCollectionID);
       await api.tx.nft
             .createItem(newCollectionID, alicesPublicKey, 'ReFungible')
             .signAndSend(alicePrivateKey);
       await waitNewBlocks(api);
       const BnftItemList = await api.query.nft.itemListIndex(newCollectionID);
-      if (BnftItemList === AnftItemList) {assert.fail('Error: new item in ReFungible collection NOT created.'); }
+      if (BnftItemList === AnftItemList) {assert.fail(`Error: new item in ${createMode} collection NOT created.`); }
     });
   });
 });