Thanks for getting back here with additional details, pshirkey.

Housecall Pro can be added in both QuickBooks Online and Desktop versions.

Any third-party apps are also sync using the QuickBooks Web Connector. Follow these steps on how to resolve common issues when looking for an app in the Manage Web Apps window:

1. Close any open windows in Web Connector. Just click the X button in the upper-right hand corner of the Web Apps window. 
2. Reopen Web Connector and check if Housecall Pro is already listed. 

If you can't still see it, I recommend reaching out to Housecall Pro. They will be the ones to help you sync QuickBooks with your Housecall account.

Let me also share these articles for additional details:

• Set Up QuickBooks Web Connector
• Fix Common Web Connector Errors in QuickBooks Desktop

Don't hesitate to add more reply and keep us posted if you're able to sync both programs. You can also