We head down to the Keys every couple of months or so. The campgrounds range from the sublime to the ridiculous in both style and price Bearing in mind there is 100miles of mostly 45mph 2 lane highway between Key Largo and Key West where you want to stay will likely, to some extent, be dictated by what you want to do whilst there. We tend always to try and book one of the 4 State parks ( Pennekamp (probably the least attractive of the 4 but very well located for scuba diving), Curry Hammock, Long Key and Bahia Honda) as our first choice. Problem with these is availability for more than a night here or a couple of nights there. Close to Key West is Bluewater RV resort ($100 or so a night) which is very impressive- not camping at all: you can have you own dock, tiki hut with ceiling fans, refrigerators etc plus all the mundane full hook up stuff....We attended the Florida State Rally at Sunshine Key Resort: did not love the campground as we were stuck in a narrow gap between a manufactured home and a very large 5th wheel but there were some very nice waterfront sites in the facility.