Reserve a car on enterprise.com ASAP to make sure they will have a car for you. If you don't, they probably won't. The fees are based on what kind of car & you can find out on the website. There is also a drop fee for one-way rentals.
If car is available you could probably pick up on 18th. Don't know rate for 1 day but shouldn't be much, depends on type of car.
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