re: Trolling Motor question

From what I’ve seen there are two main differences between saltwater and freshwater rated trolling motors.

First, the saltwater electronics are potted to keep from corroding. That just means they are encased in epoxy with adequate heat sinking rather than open circuit boards only protected by the plastic head cover.

Secondly, they have an extra layer of paint on the steel components.

Storing a boat in a rough salt-air environment would probably make it a more critical decision between the two. You should be fine.