If you put it in the water now and then, it would stay cleaner.

I keep mine year round at the St. Clair Storage Condominiums. They are also offering winter only storage with limited access that is price competitive. It is located on Marine City highway (26 mile) just 3.5 miles east of I-94. Brand new and very clean.

http://www.stclairstoragecondos.com/index.htm

If anyone's still looking my spot opened up. $125 a month but trick is mine's the last spot in the place. Must be under 8' beam and a 30' max length. This is for secured, heated storage in harrison twp.