38'+ catamarans are better, since owner and crew can be in one hull and the paying public in the other. Don't buy a new boat, but as said everything the 'guests' will lay their hands upon must always work and be operable by apes. You may need comic illustrations in the heads.
This is not a path to a Taipan's empire - may be more fun to have a beach bar that also runs day-trips to off-the-beaten-track destinations. A little weather with first-timers, or guests who bring some nascent conflict with them, can really bring on the ugly in confined spaces.