If it's the one I'm thinking of I believe the name is The Grand One Yacht. I want to say it's along the lines of $500 an hour to rent.
DH and I were asking a few questions about it one day while we were renting the little Sea Raycers. The CM offered us a tour of the yacht. Very impressive! However, I can think of a lot to do with the $$$ it cost to rent it. LOL.