Hi Tess1,
The best thing would be a refresher course, but since you can't work one in, in the 2 weeks before your trip (are you sure?-some LDS's here will,for a price,run a quick refresher course-at night,weekend,etc.)
If that can't be worked out-be sure to let the dive op you are planning to dive with (in Fl.) know-in advance- about the time lapse since you last dived. They may be able to run a brief refresher course-at least a basic skills review. Perhaps they would let you take a "resort course" as a partial refresher.
If they are 'reputable' they will ask, and may not[should not?] let you dive after a 4 yr break, unless you get a refresher course. (It sound like a strict policy, but I have seen it happen, and they are just being safe.)
Of course any refresher course is in addition to personal skill reviews, and, if you have your own gear, a thorough checkout and overhaul of it.
Please-don't just "jump in" after 4 years- too much is at stake.
good luck,
Mike