We used ProFlex RV Sealer (brussable) from Camping World and "painted" around every item on the roof. All vents, air conditioner, skylight, dish, antenna mounts and ALL previous holes. We also painted where the cabin front meets the coach. We had light rain, pouring rain and thunderstorms. NO more leaks ANYWHERE. Let me know if this helps you.
gbfankenbuy@charter.net Ken S