Depending on the length, they should run between $500.00 to $700.00. On our fifth wheel we have three any I think they are darn sure worth the money. Not only keeping debris off the slide they also keep the sun from directly off the slide keeping the trailer a little cooler and also keeping any driving rain from getting in around the seals. The only thing that I have had problems with is the wind will flap the fabric, sound like it is going to tear off the trailer. To cure that problem, just take a cotton or nylon rope and go over the topper and under the slide and snug it down to the top of the slide. Hope this helps. Happy Campin.................Ron