Here is a couple pictures of my roof after it was sealed with Flex-Armor. I have 0 leaks from the roof and guaranteed for life to never leak. This coating is 1/4 inch thick and tuff as nails. It is sprayed on hot and dries in roughly 6 seconds. They removed the vents, old caulk, A/C's etc. Then they sprayed the roof and also added some aluminum uni-strut to mount my solar panels. I can't say enough about this coating. The company in Sarasota FL. that installed this on my PC was also installing it on the city buses and school buses.
It ran around $4500, but you never have to caulk or worry about a leak from the roof ever. It also prevents most branch strikes from doing any roof damage as well. That's with in reason, if a tree falls on it obviously you may have some issues. The coating comes down over the the front and rear caps also down over the seam on the sides. I park my PC next to my workshop outside and don't worry about roof leaks. I think it was worth every dollar spent on it.