I agree that this feature should be added sooner than later into QBO. My customers ask me all the time for Credit Memos when they accidentally overpay and I have nothing to send them but a statement/payment report with "unapplied payments"  that they can use as credit in the future? it doesn't make me look good in fron tof them. The whole idea of Credit Memos is for customers to add them to their system and track their credit so they can use them when needed as well  as for us to track them to understand their origin and be able to close them by working closely/aligned with the customer. Hopefully overpayments will be able to convert to Credit Memos soon, it will definitely be helpful!