On my 1991 Ajo travel trailer the "rubber roof " was a little thicker than a heavy duty trash bag. I used eternobond tape on and around all seams and holes, then silicone white roof coating from Home Depot. Being a quick fix on an old 18 foot trailer that had no leaks but needed to last only a year or so it worked and was quick and easy and added a little weight to an already heavy trailer. It cost me about $200 for everything. If done right redoing a rubber roof is a messy dirty job and well worth doing if you are gonna keep the trailer more than 3 to 5 years. If it were me I would almost consider putting a single piece aluminum roof on if it was possible and I was going to keep it. I was not impressed with a "rubber roof" that had been in hot sun for 10 years.