Do I need to put a minus sign in front of the refund amount when when using New+ refund receipt to complete the transaction

You don't need to use a minus sign when recording a refund in QuickBooks, @info2046.

The error message "Enter a transaction amount that is 0 or greater" usually appears when the refund receipts subtotal is negative.

To resolve this, ensure the subtotal is positive when recording the refund receipt in QuickBooks.

Additionally, there are various methods available for recording customer refunds in QuickBooks. For guidance tailored to your specific scenarios, refer to this article: How to refund a customer in QuickBooks Online.

Furthermore, you can generate various sales reports to gain valuable insights into your purchases, sales, and inventory status in QuickBooks.

If you have further queries about recording refund receipts in QBO, feel free to ask on the QuickBooks Community page. We're here to help you as always.