As a note for any person trying to come to UF as an out of stater, I was one of those who did so and was able to gain residency after a couple of years. I just want to relate some of the information that I gathered about the whole process.
1. Residency is by no stretch of the imagination a guaranteed thing. There is one guy who is in charge of the whole thing, and he gets VERY PISSED at the UF law school for leading people onto thinking its easy. He told me like 3 stories of law school kids who just showed up with a form thinking they could be in and out and they'd get the in state rate.
2. You need to show and provide as many forms and paperwork you possibly can to show that you're going to stay in the state of Florida after graduation because that's basically the main reason they'll consider changing you to instate. Get the drivers license, registration, voters registration, library card, etc. Also, the MOST important thing you NEED to do is fill out a Change of Domicile Form and have it notarized the second you get an address in Florida. This is the main form that needs to be done at least a year before the deadline to change residency.
3. You really should meet with the guy in charge just so that he can put a name to the face. If you sit with him, tell a few stories, let him lecture you for awhile, you'll be good (assuming you put together a good residency application).
If you do all of these things, you'll probably get the residency, but its not guaranteed. I had a friend do WAY more than all of this but wasn't able to get residency for an extra year for no good reason. SO do yourself a favor if you're planning on becoming instate, and find every way imaginable to show you're staying in the state of Florida for good.