You don't say whether you are at a slip with access to elec or not. If you do not have access to elec. There is a product in the state available in hardward store and the like called "Damp-Rid". It comes in a variety of configuations from a hanging bag to refilable canisters. In effect it draws the moisture from the air and drains the resulting water into a bag or other container. I like the bags as they are self contained and can be hung in closets. I don't know that they would be the solution for an ongoing continous problem with dampness. You probably need to figure out the underlying cause.