Add existing estimates or invoices to projects.

Hello there, paul35. 

You can change the Customer to the Project name so the invoices or estimates will be added to the project. 

While the option to toggle sales transactions to its correct project by batch is unavailable, you'll have to manually open and change them. 

You'll want to refer to these guide articles for more information about projects: 

• Projects FAQs
• Set up and use the Projects feature

The Community is here help you with your concerns. Have a great day!