If you are charging your clients a flat fee in addition to the hourly billing, you will want to add that flat fee (with a description as to what the fee is for) to the hourly invoice. In BillQuick, this can be done in the following way:
1. From the Project screen, create a separate project (you can create it as a phase) and set that project's Contract Type as Fixed Fee.
2. Enter the scope of work or job description in the project's Memo field.
3. Next, on the Detail tab, check the rule 'Use Memo on Invoices' for this project.
4. Finally, create a joint invoice for the Hourly and Fixed Fee project in Billing Review so that they end up on the same invoice.