I have been very successful in working on the roof of my '85 Excella without scaffolding. Sometimes scaffolds are more risk than benfit. Of course a lot depends on the job at hand, your personal weight and the care that you pay to staying on the ribs. I use a ladder standing near upright on the awning, didn't like it at first, but works. I have someone hold the ladder and I wear tennis shoes. Make sure the surface is very dry and as with any task plan the tools you need, put them in a container and place them on the top of the unit. Not where you want to spend the afternoon, but I was able to do the sealing tasks, antennna replacement, vent replacement or repair without damage to me or the unit. And finally, if you feel uncomfortable, take it as a warning and let someone do it for you. One fall will pay for a lot of sealing labor. Hope this helps.