This one sounded so bazaar I had to think about it for a while. The biggest dedicated garage I have seen in a toy hauler was 10 feet in length. The toy haulers that share space with the living quarters is a little more, but still I can help but to think "WHY". That seams like a real pain in the butt way to go. I would think anyone that had a boat would simply pull it by hitch. I have never seen a anyone with a toy hauler have a boat. There are the motorcycle, and ATV crowd (who by the way started this hole mess) some golf guys with there silly golf cart, but never a boat. All toy hauler I have seen have the bed in front, it is the only practical place to have it. Also, now there are many companies that offer long goose neck auto haulers with the front living quarters. These are much more practical and provide more options as well as more room. It would be very easy to get your boat in one of these trailers, you can go as big as you and your wallet can afford. The method for getting the boas inside would be very easy. They would install a 12V electric winch and simply pull it in, the front would be supports by a trailer jack outfitted with a wheel. These units are really nothing new now days, they have come along way in a short matter of time. The options are almost endless and it ends up being unique to you and your needs.