The option to add a client's note directly while running an A/R report is not available, Teresa. However, you can use a couple of workarounds to track your collection notes.
You can add your notes directly to the customer's profile, then run a Customer Contact List report to see them. After that, you can export your A/R report to cross-reference it with the other report.

However, if your notes are specific to a single transaction, you can use the memo field on the invoice itself.
Here's how:
- Create a new invoice (or edit an existing one).
- Enter your note in the Memo on statement field.
- Save and close the invoice.
- To see these notes in a report, run the Accounts Receivable Aging Detail report.
- In the report, click Customize, go to the Rows/Columns section, and check the box for Memo to add it to your report view.

If you have other questions, feel free to comment them below.