I can personally testify that Indiantown Marina is a VERY SAFE place to dry store your boat. Several huge fields hard by the dockage basin are always dotted with hundreds of vessels resting from their voyages.
The “ash” problem Captain Jay mentions below is actually much worse farther to the west around Pahokee, Clewiston and Moore Haven. Here, when the cane fields are being burned off, the oil ash can occasionally be a real nightmare. I have seldom known this situation to be as bad at Indiantown.
Indian Town is very safe but it is in the middle of farm country especially sugar so be ready for lots of dirt and ash on your boat when you come back. If you wax it before storage it washes off with some effort.
Insurance companies that I have checked with do not give a break for safe storage but you sleep better.