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I believe there is a Marriott (or it may be a Hilton) RIGHT next to Bush Intercontinental, it's really nice and exceptionally close to the airport. There are a few cab companies with booths down by baggage claim I believe if you do not want to rent a car. I don't know where the price break is but I believe last time we cruised out of Galveston the parking was pretty easy and reasonably priced, but if you can find a good rate for a car to take you it would make things easier since they can just drop you off and then someone wont get stuck with the unfortunate task of parking the car and taking the shuttle back (it's not bad though if you have to, I think it took my Dad about 15 minutes to do it). Either way I'm sure you are going to have a great time!
