A series regular since Vice City, the Dinka Marquis sailboat shows up again in GTA 6, this time in Trailer 2. It draws on real Adjutor yachts and has always been the game's slow, graceful alternative to speedboats. Game files put it at 12,200 kg with four seats, both datamined figures. Expect leisurely cruising around Leonida's waterways rather than anything quick.
No acquisition method is confirmed. Boats in past GTA games came from marinas or in-game purchase sites, so a dock find or a boat dealer seems the realistic path. Until Rockstar details how vehicle buying works in GTA 6, treat that as expectation rather than fact.
The community companion for Grand Theft Auto VI. Database, maps, guides and tools for Vice City and the state of Leonida.