Sarasota county, FL requires that a park trailer (tiny house RV or park model RV) that stays at an RV park more than 45 consecutive days be installed with a foundation: “In RMH, OUE and OUR Zoning Districts, any park trailer that remains on site for longer than 45 consecutive days must obtain a park trailer placement permit after 45 days and be installed according to applicable codes for park trailer placement.” In a flood zone, the tiny house RV must be at least 2 feet above ground level.
Here is the link for regulations for RV parks and mobile home parks: https://www.municode.com/library/fl/sarasota_county/codes/code_of_ordinances?nodeId=APXAZORE_ART6DIDEST_6.9MAHORVPACA
Document: 6.9.___Manufactured_Homes__RV_Parks_and_Campgrounds.