IMHO, not worth anything. I bought one for my MH a few years ago. I gave it away after two or three uses. It's a real pain to put on. You have to drag a 50+ pound thing up on the roof. Drag it all the way from the rear to the front of the roof, trying not to tear it or pull something off the roof. Then pull the sides over to the side of the coach and drop them over without falling off. then climb down (no small feat with bunches of canvas falling around you) and try to get everything even and tied down. Then reverse it all when you get ready to go again. And, the winds put several holes in mine the first time I used it. When I gave it away, I had used up all the patches that came with it and had a few duct tape patches, too.
It may not have been the dumbest purchase I have made, but it certainly comes close!