To be honest with you Pro.
For the things like stripping and hanging wallpaper, (I only hang borders, but I strip everything else), I tired to base everything of an hourly rate since I work alone.
I know how much 5 yards of wallpaper boarder costs, and I know how long it takes me to hang it. So I will tell you flat out what I charge in Mid-Michigan, to hang wallpaper borders I charge 2.00 per foot.
But your wanted to know about stripping. Again I base it off of an hourly rate, and what kind of adhesive is holding the paper onto the wall. (Ive been in some older homes, where I swear thay used concrete to put the wallpaper up)
But basically for stripping borders, I charge the same that I do to put it up, 2.00 per ft.
For stripping full walls or half walls, based on what I want to make per hour, I arrived at .75¢ per sqft. (8x10 wall will cost 60.00)
But I always have a clause in the bid stating that if the wallpaper is old, or have more adhesive holding it to the wall, there will be an addtional .25¢ per sqft.
Dont misunderstand me though, I rarley hang wallpaper, just borders, so my knowledge of the actual product is dim. But I sure as hell strip alot of it in some older homes that I repaint.
Also, my prices are based for competition in my area, as I said in my above post, my buddy has a painting business 1 hour away in Detroit and he's getting almost 3 times the money I do. And he stays competitive and never hurts for business.