Renting a car from National at the San Diego airport is the easiest possible way you could ever rent a car....
Yes
No problem
Yes. Cost is based on a 24 hour period. So if you rent at 3pm you must return by 3pm tomorrow, or you will be charged a second day.
Don't see why not. I frequently have to make last minute reservations. It would also depend what they have in stock. Best to call the front desk and ask.
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