diff --git a/app/controllers/enterprises_controller.rb b/app/controllers/enterprises_controller.rb
index 2ed98b73b7..5dd1605a56 100644
--- a/app/controllers/enterprises_controller.rb
+++ b/app/controllers/enterprises_controller.rb
@@ -26,9 +26,13 @@
 # See docs/COPYRIGHT.rdoc for more details.
 #++
 class EnterprisesController < ApplicationController
+  include EnterpriseTrialHelper
+
   layout 'admin'
   menu_item :enterprise
 
+  before_action :augur_content_security_policy
+  before_action :chargebee_content_security_policy
   before_action :require_admin
   before_action :check_user_limit, only: [:show]
 
diff --git a/app/helpers/augur_helper.rb b/app/helpers/augur_helper.rb
deleted file mode 100644
index b116c2886d..0000000000
--- a/app/helpers/augur_helper.rb
+++ /dev/null
@@ -1,7 +0,0 @@
-module AugurHelper
-  def augur_content_security_policy
-    controller.append_content_security_policy_directives(
-      connect_src: %w(augur.openproject-edge.com)
-    )
-  end
-end
diff --git a/app/helpers/enterprise_trial_helper.rb b/app/helpers/enterprise_trial_helper.rb
new file mode 100644
index 0000000000..cbbec62075
--- /dev/null
+++ b/app/helpers/enterprise_trial_helper.rb
@@ -0,0 +1,15 @@
+module EnterpriseTrialHelper
+  def augur_content_security_policy
+    append_content_security_policy_directives(
+      connect_src: %w(augur.openproject-edge.com)
+    )
+  end
+
+  def chargebee_content_security_policy
+    append_content_security_policy_directives(
+      script_src: %w(js.chargebee.com),
+      style_src: %w(js.chargebee.com openproject-enterprise-test.chargebee.com),
+      frame_src: %w(js.chargebee.com openproject-enterprise-test.chargebee.com)
+    )
+  end
+end
\ No newline at end of file
diff --git a/app/views/enterprises/_info.html.erb b/app/views/enterprises/_info.html.erb
index a1965907e6..63314f1a27 100644
--- a/app/views/enterprises/_info.html.erb
+++ b/app/views/enterprises/_info.html.erb
@@ -26,16 +26,21 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 See docs/COPYRIGHT.rdoc for more details.
 
 ++#%>
-<span hidden><%= augur_content_security_policy %></span>
+<% content_for :header_tags do %>
+  <script src="https://js.chargebee.com/v2/chargebee.js"
+          data-cb-site="openproject-enterprise-test">
+  </script>
+<% end %>
 
 <p>
-  <b><%= t('js.admin.enterprise.upsale.become_hero') %></b><br> <%= t('js.admin.enterprise.upsale.you_contribute') %>
+  <b><%= t('js.admin.enterprise.upsale.become_hero') %></b><br>
+  <%= t('js.admin.enterprise.upsale.you_contribute') %>
 </p>
 
 <enterprise></enterprise>
 
 <div class="info-boxes upsale-benefits">
-  <h2>What are the benefits</h2>
+  <h2><%= t('homescreen.blocks.upsale.description') %></h2>
   <div class="info-boxes--container">
     <div class="info-boxes--item">
       <%= image_tag "https://1t1rycb9er64f1pgy2iuseow-wpengine.netdna-ssl.com/wp-content/uploads/2017/06/icon-security-features.png",
diff --git a/frontend/src/app/components/enterprise/enterprise-modal/enterprise-trial.modal.html b/frontend/src/app/components/enterprise/enterprise-modal/enterprise-trial.modal.html
index a856be6b2e..6bd3f701b7 100644
--- a/frontend/src/app/components/enterprise/enterprise-modal/enterprise-trial.modal.html
+++ b/frontend/src/app/components/enterprise/enterprise-modal/enterprise-trial.modal.html
@@ -90,8 +90,7 @@
                   <div class="form--check-box-container">
                     <input type="checkbox"
                            class="form--check-box"
-                           formControlName="newsletter_consent"
-                           (change)="receiveNewsletter($event)">
+                           formControlName="newsletter_consent">
                   </div>
                   <span>I want to receive the OpenProject
                     <a href="https://www.openproject.com/newsletter/" target="_blank">
@@ -111,6 +110,7 @@
             <span *ngIf="!confirmed; else confirmedStatus" class="status--waiting">
               email sent - waiting for confirmation
               <a id="resend-link" (click)="resendMail()">{{ text.resend }}</a>
+              <p *ngIf="cancelled">Sorry, something went wrong. Please try to resend mail.</p>
             </span>
             <ng-template #confirmedStatus>
               <span class="status--confirmed">confirmed ✓</span>
diff --git a/frontend/src/app/components/enterprise/enterprise-modal/enterprise-trial.modal.ts b/frontend/src/app/components/enterprise/enterprise-modal/enterprise-trial.modal.ts
index 502a53cd7b..0d713a7db7 100644
--- a/frontend/src/app/components/enterprise/enterprise-modal/enterprise-trial.modal.ts
+++ b/frontend/src/app/components/enterprise/enterprise-modal/enterprise-trial.modal.ts
@@ -117,8 +117,8 @@ export class EnterpriseTrialModal extends OpModalComponent {
     this.text = _.defaults(this.options.text, this.text);
   }
 
+  // checks if form is valid and submits it
   public onSubmit() {
-    // check if form is valid and handle input errors
     if (this.enterpriseTrialForm.valid) {
       this.enterpriseTrialForm.addControl('_type', new FormControl('enterprise-trial'));
 
@@ -126,15 +126,20 @@ export class EnterpriseTrialModal extends OpModalComponent {
     }
   }
 
-  public sendForm(form:FormGroup) {
+  // sends POST request with form object
+  // receives an enterprise trial link to access a token
+  private sendForm(form:FormGroup) {
+    const delay = 5000; // wait 5s until next request
+    const retries = 60; // keep trying for 5 minutes
     const trialPath = 'https://augur.openproject-edge.com/public/v1/trials';
-    // POST /public/v1/trials/ (send POST with form object)
+
+    // POST /public/v1/trials/
     this.http.post(trialPath, form)
       .toPromise()
       .then((enterpriseTrial:any) => {
         this.trialLink = enterpriseTrial._links.self.href;
 
-        this.confirmMailAddress();
+        this.retryConfirmation(delay, retries);
       })
       .catch((error:HttpErrorResponse) => {
         // mail is invalid or user already created a trial
@@ -147,7 +152,8 @@ export class EnterpriseTrialModal extends OpModalComponent {
       });
   }
 
-  public confirmMailAddress() {
+  // gets a token from the trial link if user confirmed mail
+  private getToken() {
     // 2) GET /public/v1/trials/:id
     this.http
       .get<any>(this.baseUrlAugur + this.trialLink)
@@ -161,20 +167,10 @@ export class EnterpriseTrialModal extends OpModalComponent {
       .catch((error:HttpErrorResponse) => {
         // returns error 422 while waiting of confirmation
         if (error.status === 422 && error.error.identifier === 'waiting_for_email_verification') {
-          // open next modal window
-          // status waiting
+          // open next modal window -> status waiting
           this.status = 'mailSubmitted';
-
           // get resend button link
           this.resendLink = error.error._links.resend.href;
-
-          // TODO add limit for retrying
-          setTimeout( () => {
-            // retry as long as modal is open and action is not cancelled
-            if (!this.cancelled) {
-              this.confirmMailAddress();
-            }
-          }, 5000);
         } else if (_.get(error, 'error._type') === 'Error') {
           this.notificationsService.addWarning(error.error.message);
         } else {
@@ -184,45 +180,54 @@ export class EnterpriseTrialModal extends OpModalComponent {
       });
   }
 
-  // TODO
+  // saves received token in controller
   private saveToken(token:string) {
     // POST /admin/enterprise (params[:enterprise_token][:encoded_token])
     // -> if token is new (token_retrieved: false) save token in ruby controller
     this.http.post(this.pathHelper.api.v3.appBasePath + '/admin/enterprise', { enterprise_token: { encoded_token: token } }, { withCredentials: true })
       .toPromise()
       .then((res:any) => {
-        // TODO: needs clarification: show token to copy?
         console.log('saveToken() success: ', res);
       })
       .catch((error:HttpErrorResponse) => {
         console.log('saveToken() failed: ', error.error);
+        this.notificationsService.addWarning(error.error.description || I18n.t('js.error.internal'));
       });
   }
 
-  // TODO: needs specification
+  // retries request while waiting for mail confirmation
+  private retryConfirmation(delay:number, retries:number) {
+    if (this.cancelled || this.confirmed) {
+      // stop if action was cancelled or confirmation link was clicked
+      return;
+    } else if (retries === 0) {
+      // action timed out -> show message
+      this.cancelled = true;
+    } else {
+      // retry as long as limit isn't reached
+      this.getToken();
+      setTimeout( () => {
+        this.retryConfirmation(delay, retries - 1);
+      }, delay);
+    }
+  }
+
+  // TODO: add enterprise onboarding youtube video
   public startEnterpriseTrial() {
     // open onboarding modal
     this.status = 'startTrial';
-    console.log(this.status);
-    // on continue:
-    // this.closeModal();
-    // reload page to show enterprise trial
-  }
-
-  public checkMailField() {
-    if (this.enterpriseTrialForm.value.email !== '' && this.enterpriseTrialForm.controls.email.errors) {
-      this.errorMsg = 'Invalid e-mail address';
-    } else {
-      this.errorMsg = undefined;
-    }
   }
 
+  // resends mail if resend link has been clicked
   public resendMail() {
     this.http.post(this.baseUrlAugur + this.resendLink, {})
       .toPromise()
       .then((enterpriseTrial:any) => {
         console.log('Mail has been resent.');
         this.notificationsService.addSuccess('Mail has been resent. Please check your mails and click the confirmation link provided.');
+
+        this.cancelled = false;
+        this.retryConfirmation(5000, 6);
       })
       .catch((error:HttpErrorResponse) => {
         console.log('An Error occured: ', error);
@@ -230,9 +235,13 @@ export class EnterpriseTrialModal extends OpModalComponent {
       });
   }
 
-  public receiveNewsletter(event:any) {
-    if (event.target.checked) {
-      // subscribe to newsletter
+  // checks if mail is valid after input field was edited by the user
+  // displays message for user
+  public checkMailField() {
+    if (this.enterpriseTrialForm.value.email !== '' && this.enterpriseTrialForm.controls.email.errors) {
+      this.errorMsg = 'Invalid e-mail address';
+    } else {
+      this.errorMsg = undefined;
     }
   }
 
@@ -240,7 +249,7 @@ export class EnterpriseTrialModal extends OpModalComponent {
     // cancel all actions (e.g. an already send request)
     this.cancelled = true;
     this.closeMe(event);
-    // refresh page to show trial
+    // refresh page to show enterprise trial
     if (this.status === 'startTrial' || this.confirmed) {
       window.location.reload();
     }
diff --git a/frontend/src/app/components/enterprise/enterprise.component.html b/frontend/src/app/components/enterprise/enterprise.component.html
index cb29a8f8ba..fc05b93230 100644
--- a/frontend/src/app/components/enterprise/enterprise.component.html
+++ b/frontend/src/app/components/enterprise/enterprise.component.html
@@ -1,6 +1,11 @@
 <div class='upsale--actions'>
   <button class="button -alt-highlight" (click)="openTrialModal()">{{ text.button_trial }}</button>
-  <button class="button -highlight">{{ text.button_book }}</button>
+  <a href="javascript:void(0)"
+     class="button -highlight"
+     data-cb-type="checkout"
+     data-cb-plan-id="enterprise-edition---annual-user-license">
+    {{ text.button_book }}
+  </a>
   <a href="https://www.openproject.org/upgrade-enterprise-edition/" target="_blank">
     {{ text.link_quote }}
   </a>