One does not need complicated tax shenanigans to avoid a noticeable bottom line difference in what one pays to the IRS for owning a pleasure craft. Nobody is measuring how much fuel is used for a charter versus how much was used for the owner's fishing vacation.

I have lived in Florida around boats all of my life. There are quite a few yachts 55' and longer that have a legal entity registered on Sunbiz (http://search.sunbiz.org/Inquiry/CorporationSearch/ByName) and a sign that says they are available for charter. This sign never comes out of storage.