diff --git a/.travis.yml b/.travis.yml
index e84a163..c8b8eec 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -29,7 +29,7 @@ script:
   - npm run report-coverage
   - npm run build
   - npm run doc
-  - ./src/examples/fire_lazers.sh
+  - npm run integration
 
 after_script:
   - greenkeeper-lockfile-upload
diff --git a/package.json b/package.json
index 9dab4c7..14290a4 100644
--- a/package.json
+++ b/package.json
@@ -8,6 +8,7 @@
     "test": "mocha",
     "test:watch": "mocha -w --watch-extensions js,ts,json",
     "test:cover": "nyc mocha",
+    "integration": "./src/examples/fire_lazers.sh",
     "clean": "rm -rf ./dist/ ./doc/ ./coverage ./.nyc_output",
     "lint": "tslint -c tslint.json 'src/**/*.ts' 'test/**/*.ts'",
     "start": "npm link @oceanprotocol/keeper-contracts @oceanprotocol/secret-store-client && npm run build:watch",
diff --git a/src/brizo/Brizo.ts b/src/brizo/Brizo.ts
index 58c97f1..b92ac60 100644
--- a/src/brizo/Brizo.ts
+++ b/src/brizo/Brizo.ts
@@ -42,12 +42,15 @@ export default class Brizo {
             consumerAddress,
         }
 
-        return WebServiceConnectorProvider
-            .getConnector()
-            .post(
-                this.getPurchaseEndpoint(),
-                decodeURI(JSON.stringify(args)),
-            )
-
+        try {
+            return await WebServiceConnectorProvider
+                .getConnector()
+                .post(
+                    this.getPurchaseEndpoint(),
+                    decodeURI(JSON.stringify(args)),
+                )
+        } catch (e) {
+            throw new Error("HTTP request failed")
+        }
     }
 }
diff --git a/src/examples/BuyAsset.ts b/src/examples/BuyAsset.ts
index 9d59078..a50c0fb 100644
--- a/src/examples/BuyAsset.ts
+++ b/src/examples/BuyAsset.ts
@@ -5,8 +5,9 @@ import Service from "../ddo/Service"
 import DID from "../ocean/DID"
 import {Account, Logger, Ocean, ServiceAgreement} from "../squid"
 import config from "./config"
+import {runner} from "./runner"
 
-(async () => {
+async function exec() {
     const ocean: Ocean = await Ocean.getInstance(config)
 
     const publisher: Account = (await ocean.getAccounts())[0]
@@ -68,6 +69,6 @@ import config from "./config"
 
     const paid = await serviceAgreement.payAsset(did.getId(), metaData.base.price, consumer)
     Logger.log(`Asset paid: ${paid}`)
+}
 
-    process.exit(0)
-})()
+runner(exec)
diff --git a/src/examples/ExecuteAgreement.ts b/src/examples/ExecuteAgreement.ts
index 7dd5d8d..9a3fe2b 100644
--- a/src/examples/ExecuteAgreement.ts
+++ b/src/examples/ExecuteAgreement.ts
@@ -4,8 +4,9 @@ import MetaDataBase from "../ddo/MetaDataBase"
 import Service from "../ddo/Service"
 import {Account, Logger, Ocean, ServiceAgreement} from "../squid"
 import config from "./config"
+import {runner} from "./runner"
 
-(async () => {
+async function exec() {
     const ocean: Ocean = await Ocean.getInstance(config)
 
     const publisher: Account = (await ocean.getAccounts())[0]
@@ -63,6 +64,6 @@ import config from "./config"
         consumer,
         publisher)
     Logger.log("ServiceAgreement Id:", serviceAgreement.getId())
+}
 
-    process.exit(0)
-})()
+runner(exec)
diff --git a/src/examples/GetAccounts.ts b/src/examples/GetAccounts.ts
index 9f14d23..94639b9 100644
--- a/src/examples/GetAccounts.ts
+++ b/src/examples/GetAccounts.ts
@@ -1,12 +1,13 @@
 import {Logger, Ocean} from "../squid"
 import config from "./config"
+import {runner} from "./runner"
 
-(async () => {
+async function exec() {
     const ocean: Ocean = await Ocean.getInstance(config)
 
     const accounts = await ocean.getAccounts()
 
     Logger.log(JSON.stringify(accounts, null, 2))
+}
 
-    process.exit(0)
-})()
+runner(exec)
diff --git a/src/examples/GetBalance.ts b/src/examples/GetBalance.ts
index 308f8b4..58619a1 100644
--- a/src/examples/GetBalance.ts
+++ b/src/examples/GetBalance.ts
@@ -1,12 +1,13 @@
 import {Logger, Ocean} from "../squid"
 import config from "./config"
+import {runner} from "./runner"
 
-(async () => {
+async function exec() {
     const ocean: Ocean = await Ocean.getInstance(config)
 
     const accounts = await ocean.getAccounts()
 
     Logger.log(await accounts[0].getBalance())
+}
 
-    process.exit(0)
-})()
+runner(exec)
diff --git a/src/examples/GetHDWalletAccounts.ts b/src/examples/GetHDWalletAccounts.ts
index 9f14d23..94639b9 100644
--- a/src/examples/GetHDWalletAccounts.ts
+++ b/src/examples/GetHDWalletAccounts.ts
@@ -1,12 +1,13 @@
 import {Logger, Ocean} from "../squid"
 import config from "./config"
+import {runner} from "./runner"
 
-(async () => {
+async function exec() {
     const ocean: Ocean = await Ocean.getInstance(config)
 
     const accounts = await ocean.getAccounts()
 
     Logger.log(JSON.stringify(accounts, null, 2))
+}
 
-    process.exit(0)
-})()
+runner(exec)
diff --git a/src/examples/GrantAccess.ts b/src/examples/GrantAccess.ts
index ecc2237..1430d55 100644
--- a/src/examples/GrantAccess.ts
+++ b/src/examples/GrantAccess.ts
@@ -5,8 +5,9 @@ import Service from "../ddo/Service"
 import DID from "../ocean/DID"
 import {Account, Logger, Ocean, ServiceAgreement} from "../squid"
 import config from "./config"
+import {runner} from "./runner"
 
-(async () => {
+async function exec() {
     const ocean: Ocean = await Ocean.getInstance(config)
 
     const publisher: Account = (await ocean.getAccounts())[0]
@@ -71,6 +72,6 @@ import config from "./config"
 
     const accessGranted = await serviceAgreement.grantAccess(did.getId(), did.getId(), publisher)
     Logger.log(`Asset access granted: ${accessGranted}`)
+}
 
-    process.exit(0)
-})()
+runner(exec)
diff --git a/src/examples/InitializeAgreement.ts b/src/examples/InitializeAgreement.ts
index e936312..541d637 100644
--- a/src/examples/InitializeAgreement.ts
+++ b/src/examples/InitializeAgreement.ts
@@ -4,8 +4,9 @@ import MetaDataBase from "../ddo/MetaDataBase"
 import Service from "../ddo/Service"
 import {Account, Logger, Ocean} from "../squid"
 import config from "./config"
+import {runner} from "./runner"
 
-(async () => {
+async function exec() {
     const ocean: Ocean = await Ocean.getInstance(config)
 
     const publisher: Account = (await ocean.getAccounts())[1]
@@ -57,15 +58,19 @@ import config from "./config"
 
     const service: Service = ddo.findServiceByType("Access")
 
-    await ocean
-        .initializeServiceAgreement(
-            ddo.id,
-            service.serviceDefinitionId,
-            serviceAgreementSignatureResult.serviceAgreementId,
-            serviceAgreementSignatureResult.serviceAgreementSignature,
-            (files) => Logger.log(`Got files, first files length in bytes: ${files[0].length}`),
-            consumer,
-        )
+    try {
+        await ocean
+            .initializeServiceAgreement(
+                ddo.id,
+                service.serviceDefinitionId,
+                serviceAgreementSignatureResult.serviceAgreementId,
+                serviceAgreementSignatureResult.serviceAgreementSignature,
+                (files) => Logger.log(`Got files, first files length in bytes: ${files[0].length}`),
+                consumer,
+            )
+    } catch (e) {
+        throw new Error(`"Error on initializeServiceAgreement: ${e}`)
+    }
+}
 
-    process.exit(0)
-})()
+runner(exec)
diff --git a/src/examples/RegisterAsset.ts b/src/examples/RegisterAsset.ts
index 2b91a8e..483b089 100644
--- a/src/examples/RegisterAsset.ts
+++ b/src/examples/RegisterAsset.ts
@@ -3,8 +3,9 @@ import MetaData from "../ddo/MetaData"
 import MetaDataBase from "../ddo/MetaDataBase"
 import {Account, Logger, Ocean} from "../squid"
 import config from "./config"
+import {runner} from "./runner"
 
-(async () => {
+async function exec() {
     const ocean: Ocean = await Ocean.getInstance(config)
 
     const publisher: Account = (await ocean.getAccounts())[0]
@@ -41,6 +42,6 @@ import config from "./config"
 
     const ddo: DDO = await ocean.registerAsset(metaData, publisher)
     Logger.log(ddo.id)
+}
 
-    process.exit(0)
-})()
+runner(exec)
diff --git a/src/examples/RegisterServiceAgreementTemplates.ts b/src/examples/RegisterServiceAgreementTemplates.ts
index 3a3e03f..e54d84c 100644
--- a/src/examples/RegisterServiceAgreementTemplates.ts
+++ b/src/examples/RegisterServiceAgreementTemplates.ts
@@ -1,7 +1,8 @@
 import {Account, Logger, Ocean, ServiceAgreementTemplate, Templates} from "../squid"
 import config from "./config"
+import {runner} from "./runner"
 
-(async () => {
+async function exec() {
     const ocean: Ocean = await Ocean.getInstance(config)
 
     const templateOwner: Account = (await ocean.getAccounts())[0]
@@ -11,6 +12,6 @@ import config from "./config"
 
     Logger.log("ServiceAgreementTemplate registered:", serviceAgreementRegistered,
         "templateId:", serviceAgreementTemplate.getId())
+}
 
-    process.exit(0)
-})()
+runner(exec)
diff --git a/src/examples/Search.ts b/src/examples/Search.ts
index 8f41312..edb9e89 100644
--- a/src/examples/Search.ts
+++ b/src/examples/Search.ts
@@ -1,8 +1,9 @@
 import DDO from "../ddo/DDO"
 import {Logger, Ocean} from "../squid"
 import config from "./config"
+import {runner} from "./runner"
 
-(async () => {
+async function exec() {
     const ocean: Ocean = await Ocean.getInstance(config)
 
     const result: DDO[] = await ocean.searchAssetsByText("Office Humidity")
@@ -14,6 +15,6 @@ import config from "./config"
     })
 
     Logger.log(names.length, names)
+}
 
-    process.exit(0)
-})()
+runner(exec)
diff --git a/src/examples/SignAgreement.ts b/src/examples/SignAgreement.ts
index 0b9d792..a1e8d2a 100644
--- a/src/examples/SignAgreement.ts
+++ b/src/examples/SignAgreement.ts
@@ -6,8 +6,9 @@ import MetaDataBase from "../ddo/MetaDataBase"
 import Service from "../ddo/Service"
 import {Account, Logger, Ocean} from "../squid"
 import config from "./config"
+import {runner} from "./runner"
 
-(async () => {
+async function exec() {
     const ocean: Ocean = await Ocean.getInstance(config)
 
     const publisher: Account = (await ocean.getAccounts())[0]
@@ -77,6 +78,6 @@ import config from "./config"
 
     Logger.log("ServiceAgreement Id:", serviceAgreementResult.serviceAgreementId)
     Logger.log("ServiceAgreement Signature:", serviceAgreementResult.serviceAgreementSignature)
+}
 
-    process.exit(0)
-})()
+runner(exec)
diff --git a/src/examples/runner.ts b/src/examples/runner.ts
new file mode 100644
index 0000000..0d0a631
--- /dev/null
+++ b/src/examples/runner.ts
@@ -0,0 +1,10 @@
+import {Logger} from "../squid"
+
+export function runner(fn: () => Promise<any>) {
+    fn()
+        .then(() => process.exit(0))
+        .catch((e) => {
+            Logger.error(e)
+            process.exit(1)
+        })
+}
diff --git a/src/keeper/Event.ts b/src/keeper/Event.ts
index 6dc4207..cf30fa6 100644
--- a/src/keeper/Event.ts
+++ b/src/keeper/Event.ts
@@ -1,7 +1,7 @@
+import Logger from "../utils/Logger"
 import GenericContract from "./contracts/GenericContract"
 import EventListener from "./EventListener"
 import Web3Provider from "./Web3Provider"
-// import Logger from "../utils/Logger"
 
 export default class Event {
 
@@ -40,6 +40,9 @@ export default class Event {
     private async handler(callback: any) {
         const contract = await GenericContract.getInstance(this.contractName)
 
+        if (this.lastBlock > await Web3Provider.getWeb3().eth.getBlockNumber()) {
+            return
+        }
         try {
             const events = await contract.getEventData(this.eventName, {
                 filter: this.filter,
@@ -52,7 +55,7 @@ export default class Event {
                 callback(events)
             }
         } catch (err) {
-            // Logger.log("err")
+            Logger.log(err)
         }
     }
 }
diff --git a/src/keeper/contracts/ContractBase.ts b/src/keeper/contracts/ContractBase.ts
index 1b23262..2dc88fc 100644
--- a/src/keeper/contracts/ContractBase.ts
+++ b/src/keeper/contracts/ContractBase.ts
@@ -63,8 +63,12 @@ export default abstract class ContractBase {
                     value: args[i],
                 }
             })
+            Logger.error("-".repeat(40))
             Logger.error(`Sending transaction "${name}" on contract "${this.contractName}" failed.`)
-            Logger.error(`Parameters: ${JSON.stringify(mappedArgs, null, 2)} from: ${from}`)
+            Logger.error(`Error: ${err.message}`)
+            Logger.error(`From: ${from}`)
+            Logger.error(`Parameters: ${JSON.stringify(mappedArgs, null, 2)}`)
+            Logger.error("-".repeat(40))
             throw err
         }
     }
diff --git a/src/ocean/Account.ts b/src/ocean/Account.ts
index 4a44188..1473488 100644
--- a/src/ocean/Account.ts
+++ b/src/ocean/Account.ts
@@ -3,6 +3,7 @@ import * as EthJsUtils from "ethereumjs-util"
 import Keeper from "../keeper/Keeper"
 import Web3Provider from "../keeper/Web3Provider"
 import Balance from "../models/Balance"
+import Logger from "../utils/Logger"
 import OceanBase from "./OceanBase"
 
 /**
@@ -57,9 +58,15 @@ export default class Account extends OceanBase {
      * @return {Promise<number>}
      */
     public async requestTokens(amount: number): Promise<number> {
-        await (await Keeper.getInstance())
-            .market
-            .requestTokens(amount, this.id)
+        try {
+            await (await Keeper.getInstance())
+                .market
+                .requestTokens(amount, this.id)
+        } catch (e) {
+            Logger.error(e)
+            throw new Error("Error requesting tokens")
+
+        }
         return amount
     }
 
diff --git a/src/ocean/Ocean.ts b/src/ocean/Ocean.ts
index c06d592..5045f1e 100644
--- a/src/ocean/Ocean.ts
+++ b/src/ocean/Ocean.ts
@@ -245,11 +245,10 @@ export default class Ocean {
             const event: ContractEvent = EventListener.subscribe(
                 accessService.serviceAgreementContract.contractName,
                 accessService.serviceAgreementContract.events[0].name, {
-                    serviceAgreementId,
+                    serviceAgreementId: `0x${serviceAgreementId}`,
                 })
 
             event.listenOnce(async (data) => {
-
                 const sa: ServiceAgreement = new ServiceAgreement(data.returnValues.serviceAgreementId)
                 await sa.payAsset(
                     d.getId(),
@@ -263,7 +262,6 @@ export default class Ocean {
                 serviceAgreementId,
                 serviceAgreementSignature,
             }
-
         } catch (err) {
             Logger.error("Signing ServiceAgreement failed!", err)
         }
@@ -296,24 +294,26 @@ export default class Ocean {
         const accessEvent: ContractEvent = EventListener.subscribe(
             accessService.conditions[1].contractName,
             accessService.conditions[1].events[1].name, {})
+        const filesPromise = new Promise((resolve) => {
+            accessEvent.listenOnce(async () => {
+                Logger.log("Awesome; got a AccessGranted Event. Let's download the asset files.")
+                const contentUrls = await SecretStoreProvider
+                    .getSecretStore()
+                    .decryptDocument(d.getId(), metadataService.metadata.base.contentUrls[0])
+                const serviceUrl: string = accessService.serviceEndpoint
+                Logger.log("Consuming asset files using service url: ", serviceUrl)
+                const files = []
 
-        accessEvent.listenOnce(async () => {
-            Logger.log("Awesome; got a AccessGranted Event. Let's download the asset files.")
-            const contentUrls = await SecretStoreProvider
-                .getSecretStore()
-                .decryptDocument(d.getId(), metadataService.metadata.base.contentUrls[0])
-            const serviceUrl: string = accessService.serviceEndpoint
-            Logger.log("Consuming asset files using service url: ", serviceUrl)
-            const files = []
+                for (const cUrl of contentUrls) {
+                    let url: string = serviceUrl + `?url=${cUrl}`
+                    url = url + `&serviceAgreementId=${serviceAgreementId}`
+                    url = url + `&consumerAddress=${consumer.getId()}`
+                    files.push(url)
+                }
 
-            for (const cUrl of contentUrls) {
-                let url: string = serviceUrl + `?url=${cUrl}`
-                url = url + `&serviceAgreementId=${serviceAgreementId}`
-                url = url + `&consumerAddress=${consumer.getId()}`
-                files.push(url)
-            }
-
-            cb(files)
+                cb(files)
+                resolve(files)
+            })
         })
 
         await BrizoProvider
@@ -324,6 +324,8 @@ export default class Ocean {
                 serviceDefinitionId,
                 serviceAgreementSignature,
                 consumer.getId())
+
+        await filesPromise
     }
 
     /**
diff --git a/src/ocean/ServiceAgreements/ServiceAgreementTemplate.ts b/src/ocean/ServiceAgreements/ServiceAgreementTemplate.ts
index ae6423d..9621ae8 100644
--- a/src/ocean/ServiceAgreements/ServiceAgreementTemplate.ts
+++ b/src/ocean/ServiceAgreements/ServiceAgreementTemplate.ts
@@ -58,15 +58,21 @@ export default class ServiceAgreementTemplate extends OceanBase {
             return false
         }
 
-        const receipt = await serviceAgreement
-            .setupAgreementTemplate(
-                this.template.id,
-                await this.getMethodReflections(),
-                dependencyMatrix,
-                Web3Provider.getWeb3().utils.fromAscii(this.template.templateName),
-                fulfillmentIndices,
-                this.template.fulfillmentOperator,
-                templateOwnerAddress)
+        let receipt
+        try {
+            receipt = await serviceAgreement
+                .setupAgreementTemplate(
+                    this.template.id,
+                    await this.getMethodReflections(),
+                    dependencyMatrix,
+                    Web3Provider.getWeb3().utils.fromAscii(this.template.templateName),
+                    fulfillmentIndices,
+                    this.template.fulfillmentOperator,
+                    templateOwnerAddress)
+        } catch (e) {
+            Logger.error(e)
+            throw new Error(`Is not possible to setup the agreement template`)
+        }
 
         const {serviceTemplateId, provider} = receipt.events.SetupAgreementTemplate.returnValues
 
diff --git a/src/utils/WebServiceConnector.ts b/src/utils/WebServiceConnector.ts
index ae73194..3566e0c 100644
--- a/src/utils/WebServiceConnector.ts
+++ b/src/utils/WebServiceConnector.ts
@@ -1,11 +1,12 @@
 import fetch, { BodyInit, RequestInit, Response } from "node-fetch"
+import Logger from "./Logger"
 
 /**
  * Provides a common interface to web services.
  */
 export default class WebServiceConnector {
 
-    public async post(url: string, payload: BodyInit): Promise<Response> {
+    public post(url: string, payload: BodyInit): Promise<Response> {
         return this.fetch(url, {
             method: "POST",
             body: payload,
@@ -15,7 +16,7 @@ export default class WebServiceConnector {
         })
     }
 
-    public async get(url: string): Promise<Response> {
+    public get(url: string): Promise<Response> {
         return this.fetch(url, {
             method: "GET",
             headers: {
@@ -24,7 +25,7 @@ export default class WebServiceConnector {
         })
     }
 
-    public async put(url: string, payload: BodyInit): Promise<Response> {
+    public put(url: string, payload: BodyInit): Promise<Response> {
         return this.fetch(url, {
             method: "PUT",
             body: payload,
@@ -35,6 +36,12 @@ export default class WebServiceConnector {
     }
 
     private async fetch(url: string, opts: RequestInit): Promise<Response> {
-        return fetch(url, opts)
+        const result = await fetch(url, opts)
+        if (!result.ok) {
+            Logger.error(`Error requesting [${opts.method}] ${url}`)
+            Logger.error(`Response message: \n${await result.text()}`)
+            throw result
+        }
+        return result
     }
 }