I lived on a boat in college, (University of Maryland-Baltimore). It was not mine but I rented it for about a year and a half. The owner was always traveling around the world and originally wanted someone to watch his big boat while he was out of town but I told him I could not be moving in and out all the time trying to fit his travel schedule so he just rented it to me and the marina slip was included. All I did was pay the rent and buy my own food and kept an eye on his boat of course...
The only down side was when a storm came in, the water can get a little rough at times but when the storms were really bad, I just pulled up anchor and took the boat down the coast a ways out of the path of the storm and after the storm I came back to the marina again.
The up side was that everyone thought WOW what a great place to live, a big fancy luxury yacht, so I was always the hit with all my friends. It had a full galley and big screen TV with satellite...everything a young college student needed. Because I lived on the boat, I had free parking at the marina so there were no other expenses other than my rent each month, which was pretty cheap because the rent was offset by the fact the owner was actually paying me to watch his boat and I just had him put it towards my rental fees.