I have often to leave in the early morning. In order to avoid bad surprises (e.g. some agents need >15min to only change the address, e.g. from private to company or customer address), I regularly pay during the evening before ... No hassle in the morning. Everything is right on the receipt and if I have anything more during the night (e.g. minibar, room service), I'm 100% sure that the address on the receipt is already correct and it will be a short stop at the reception to pay the rest.
Fire_Fly, I'd suggest to do the same: pay after your lunch/dinner. Nobody will notice when you actually leave and you have the receipt.
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