We have done the same thing for a few years. We had two trailers (fivers) and then switched to a small motorhome. This advice is from my perspective. Maybe it won't fit yours. But we are almost at this point:
If the only real usage is going to be for the snowbird trip, I no longer want to drive or drag an RV back and forth. Leave it there! I thought we were going to be doing a lot of other traveling besides the snowbird thing. In reality, the snowbird thing is a big chunk of the year, so the rest of the time we aren't as interested in RV travel. It's easy to tell yourself, we'll get this trailer and we'll go all over with it. But will you? Or will you just drag it back and forth to Florida?
You mention Carolina to Florida. Anything north of FL will have some serious cold weather, too cold for a snowbird experience, IMO.