When we park for extended periods of time, particularly near the ocean, we disconnect and drive someplace like a winery or some other attraction which keeps the rust from becoming a problem. We also hose the salt off the coach surfaces which also takes care of the bird droppings. Spraying a barrier on exposed metal brake surfaces is generally not a good idea since it diminishes the adhesion between the rotor and the pad. Moving the tires is a great idea. I would extend that nicety to the rest of the coach to keep the salt air from intruding into the coach through open windows, ceiling fans, and engine. Suggest while you are enjoying the view you wipe down a section of the outside surfaces with Protectall or, better yet, 303. Don't fall off the roof.