Hard water stain
I think I saw the answer to this once, but can't find it now or remember the solution.....When running the rooftop AC, water will trickle off the roof(normal) and run down the side of the coach leavin...
Forum Discussion
I would avoid anything abrasive such as rubbing compound or soft scrub, at least on a continual basis. Try the vinegar and, once clean, apply a good wax.
