No, they do not have rentals there. You would have to take a taxi to a local car rental.
Yes
You can equally booked a limo service to come pick you up to Virginia. One of such reliable limo service is "A Touch of Class limousines" based in Frederick, MD.
I'm sure you could make arrangements with enterprise to drop off a car. Not sure what it would cost but just inquire.
I don't remember seeing any car rentals at the terminal.
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