Hello there, @tonetone. You can use a sales receipt since you immediately received a check payment after rendering your service. Just ensure it's deposited to Payments to Deposit (Undeposited Funds). That way, it stays tucked away in your records until you’re ready to head to the bank at the end of the month.
An invoice, on the other hand, would be a better choice only if your customers plan to pay at a later date.

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