Adding amount to be invoiced to the project customer (T&M)
Solution for Time & Material project. For Fixed-price project see this article.
Open your project and choose Fee under Journals in the Project menu

Choose New and give a Description

Choose Lines. And give a description and the sales price.

Choose Financial dimensions and add the correct values.

Click OK, Then chose Post

Now, you will find these “Fee lines” together with other billable project transactions when creating a new Invoice proposal.