Experience, training or licensing may be needed
Boats that are hauled out of the water for the winter or even just for mid-season repairs will need the hull cleaned. And depending on the type of boat, it is a good time to give a major cleaning everything else too–the decks, the sleeping quarters, the head, and the holds. Start by approaching homes that have a boat sitting in the yard. Or you could market your services to the marina to contract you to do the boat cleaning it offers to customers.