Hi there, roystallard.

I'd like to join this discussion and provide additional insight.

After some thorough research and testing, I found that the simplest and most accurate way to verify this is to go to your customer's Transaction List. Then, double-click the invoice that was created for the billable items to open it up. In here, you can check that all the relevant purchases are included.

Here's how you can get there:

1. From the Customers menu, choose Customer center.
2. Select the customer's name.

Lastly, you may go back to the Transaction List and check other invoices to make sure it hasn't been duplicated. You may also pull up the Unbilled Costs by Job report, but this will only show you which items were marked as billable that hasn't been invoiced yet. Here's how you can pull it up:

1. From the Reports menu, select Jobs, Time & Mileage, then Unbilled Costs by Job.
2. Click the Customize Report button.
3. Change the From and To date as necessary.
4. In the Columns section, search for the Item column, then select it.
5. Click OK, then Done.

That should do it. Please let me know if there's anything else I can do for you. I'm always happy to help.