Charging it as part of closing the rental. Generally I land at airports where the check-in team has hand-scanners… they scan the car as they do a walk-around, look the car over, confirm my name, remind me to grab personal belongings and leave the keys in the car… and send me the receipt by email.

I now make it a practice to NOT leave the rental return area until I’ve seen the receipt and verify that the balance is what I expected. It’s easier to fix it when you’re standing there. It would appear that they fix it by adjusting the “pending” charge… not by issuing a refund… ultimately, the corrected amount is what posts to the statement.