Thank you for participating in this thread, Ashley1245. 

As mentioned by my colleague KimberlyS, we can pull up the Transaction List with Split report to show your customers' billable expenses. Here's how:

1. On the Reports, search for the Transaction list with Splits.
2. Click Customize. Under Rows/Columns, click Change columns and check Billable.
3. Press Filter, and under Transaction type, click Bill and Billable Expense Charge.
4. Click Run report.

I've added a screenshot for your visual reference.

In addition, you may check this article to guide you on how to modify your reports: Customize reports in QuickBooks Online.

Also, you can visit this page if you want to learn how to enter a prior balance for a customer who owes you money or a vendor you need to pay: Manage outstanding balances for customers and vendors in QuickBooks Online.

If you need help with running reports, just let us know. We're always available to assist you. Take care.