Hi Shane and welcome to the forum.

To rent a car in Florida, you'll get the best deal with the website you can see up this page: click on "florida car hire". They do other parts of the US too if you need a car on the other parts of your trip. We're going to Kansas after Florida and they're cheaper there too.

21 hours, wow... you certainly do hope you'll get good inflight entertainment and food [msnwink]...

Nathalie.