I figure it wouldn't be much problem, but when I checked the prices online now and called the customer service, to make the pick up time 2 hours earlier would have changed our rental price from $275 to close to $600. Just for a 2 hour change!!! I don't know how I got such a good rate for the Midsize SUV for the start of the summer vacation 2013, but at this point I will certainly keep the reservation and put on the charm to get the car early.