Dollar charged me an early return fee of $15 because I brought the car back 3 hours before the due date on the contract. There is no possible cost to Dollar that would justify the fee. I'm sure they had the car back on the road within the hour!
The rental office at the Denver airport is also understaffed ( I waited over 30 minutes to get to a rep) and then they told me that no car of the class I had rented was available and made me wait an additional 30 minutes for one to "become available." Dollar then gave me the keys to a car (of the same rental class as the one I reserved) that had been sitting in the lot the whole time I was in the rental office. When I asked why I had had to wait a half hour for a car that was already available, the guy just shrugged his shoulders and smiled.
Bottom line: I will never rent from Dollar again.