The Dominator Buggy is a mud-club car with off-road handling for Mount Kalaga. You store it at Paradise Garage in Watson Bay. That garage has a gun locker and a place to have stolen goods traded.
Rockstar calls it 'a Mud Club monster offering impressive off-road handling for the backwoods of Mount Kalaga and beyond.' The Dominator name usually belongs to Vapid's muscle car. This 1967 version is a buggy built for mud.
It is the Ultimate vehicle that comes with a garage of its own: Paradise Garage in Watson Bay, with a weapon locker and a place to fence stolen goods.