pretty much any boat 27 feet or longer, but try em on for size first, as some boats are bigger for length. i would start with early 80's hunters catalinas, etc.
a boat would be much cheaper, figure 10 grand for a decent ( not great but decent ) early 80's 27 to 30 foot boat. then slip fees from 2 to 4 grand a year plus the electric is nothing compared to a house. other fees like pulling it out for paint, winter and other stuff might be 500 a year ( dry storage figured in the slip fee ). then figure 2 to 4 grand a year in paint and other maintenance, which will be more than a house needs.
so yearly cost not including the boat will be 4 to 6 grand, so high end it will average 500 to 600 a month, or equivalent to a 80,000 mortgage. the nice thing with a boat it you can move it when you want a different view.
now you could get away cheaper some years, some it might be more