Cleaning an epdm roof

You guys really have got the roof subject down to a science. For me, I have had my trusted dealer wash and exam the roof for the last two years. I bought the trailer in 2011 new.The dealer took pics of the roof each year and we would discuss if anything should be done. In the past years we decided the cracks were not bad enough. This year was different. We went ahead with repairs. The sun can get pretty brutal where we live.They took off the old caulking and then used a tube of lap sealant W leveling, and a lap sealant white non leveling. These are Dicor products.It took them just under 4 hours.The cost was around $500.