Collections Report/Open Invoices for Specific Month's Billing

I've got two reports that display the data you need, Barryb.

You can run the Invoice List and the Open Invoices reports. The first one shows both the paid and unpaid invoices, while the latter is only for the unpaid ones.

To open and customize the Invoice List report:

1. Click Reports on the left panel.
2. Type Invoice List on the search box.
3. Click the Customize button in the upper right-hand corner.
4. Maximize the Rows/Columns section, and then click the Change columns link.
5. Check the box for A/R Paid.
6. Maximize the Filters section, and then check the box for A/R Paid. If you want the report to show both the paid and unpaid ones, just select All. If not, just click Paid and run the Open Invoices report to get the data for the unpaid transactions (see steps below). 
7. Filter the Report period.
8. Click Run report.

Here's how to run the Open Invoices report:

1. Click Reports on the left panel.
2. Type Open Invoices on the search box.
3. Follow step 7 above.

If you want to print these reports, please let me know so I can give you the steps. Happy New Year!