Walls-repair/cleaning/painting or wallpapering

by Sharon

I have some questions about the walls in my 98 bella vista. I was told when i bought it from the dealer that the walls were not wood nor sheetrock. That the printed design on the walls was not wallpaper that it was actually part of the wall. What are the walls made of then? I have a hole in one wall that I want to fix. It seems to be some kind of compressed particle board? What steps do I need to take to repair the hole? I also have noticed that over the last 12 years or so that the walls have discolored and stains are not easily removed. when i tried to clean a section of the wall the printed design on the wall just got lighter. Is there a special product I shoulod be using? I also want to know if painting the walls is possible, how big of a project it will be and if there are any special steps i must take before applying the paint?