Maintenance

Cut costs by washing down your boat with freshwater after each use. Even then, you'll need to repaint the bottom of the boat with anti-fouling paint every year (about $30 per foot, according to Collins). If you have a sailboat, plan on replacing the sails every three to five years. With powerboats, you'll need to check and service the engines more frequently. Little extras add up -- everything from about $300 per year for cleaners and soaps to several hundred dollars on waxing the hull and treating fabric.