Go to apps.com here you will see a full list of apps that sync with QBO, some shopping cart apps require a third party to sync and they charge extra.

Resolution for 'charge extra issue: 'Can we integrate QuickBooks with an App for E-Commerce (such as Open Cart) and also with apps for Email Marketing (Such as MailChimp)?' available: Yes.

The charge extra issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the charge extra issue yourself by looking for a resolution described in the article. If it is a complex charge extra issue or you are unable to solve the issue, you may contact us by clicking here or by using other charge extra support options.

For more information about resolving issues related to charge extra in Quickbooks/QBO or to get support for the issue 'Can we integrate QuickBooks with an App for E-Commerce (such as Open Cart) and also with apps for Email Marketing (Such as MailChimp)?', click the link below: