South of I-4 along US27 you will find some possibilities. 2 years ago we didn't leave Michigan until February 1st, without reservations other than one place down in the Keys and we stayed at 8 different campgrounds from north to south. Depending upon any amenities you might be looking for, there will be parks for you.
Sebring is a nice area. We stayed at a place called Whispering Pines there for a couple of days. They had plenty of sites available for a very reasonable price. Sites were a little tight, but the residents were nice as were the managers. Below is a clicky for Sebring at RV Park Reviews.com. This will list the park I've noted above as well as others in that area with camper ratings and comments.
http://www.rvparkreviews.com/regions/florida/sebringAnother park we stayed at for a few days was in Winter Haven, Cypress Campground & RV Park. We wanted to stay in that area to attend a Detroit Tiger spring game in Lakeland. See the clicky for the Winter Haven area.
http://www.rvparkreviews.com/regions/florida/winter-havenBoth these places had pools, activities, and were fairly priced. As I said, we stayed only a few days in each location because we were trying to visit several parks for a few days each to see the area as well as the parks themselves. Not sure what they are like for the long term.
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