I have a potential client that uses HoneyBooks. Does anyone know if it integrates with QBO Cda?

It supports QBO US version for sure. You have to contact HoneyBooks if they support other regions.

https://help.honeybook.com/en/articles/2209137-which-quickbooks-versions-and-plans-will-connect-with-honeybook

Hello rhunter33. Just to add to the valuable info 4Gal has shared above, you can also search for third-party integration apps on our site www.apps.com. I recommend choosing an app that suits your business needs based on the app description and reviews. Let me know if you have other questions. I'm here to help.