That receipt will note the time when the car was returned, the odometer mileage, and the fuel gauge reading. No later than the next morning, the customer service folks at the Dolphin will process your return and email you a copy of the rental receipt showing the final charges. Sometimes, I have received this email on my phone while walking back to the Boardwalk, so someone from Alamo must have been available when the valet delivered a copy of the receipt to them, but if it is well after the 4 pm closing time, this is much less likely to happen. I have always been charged the amount agreed to in my rental contract.