Our pantry and cupboards were so nasty I don't know how anyone even put food or dishes in them! It took me two weeks, a lot of bleach and finally two coats of paint in them before I finally put stuff in them and was able to eat here.
As for the room with the massive amount of wallpaper-
We spent 3 days off and on trying to get it off and tried many different things that people told us to try or we found online and that stuff was stuck! So my husband read somewhere that we should sand it down smooth, put a couple coats of oil based primer "which is sticky and hard to get off your skin" and then he re-textured the whole room. Yes it cost a bit more but we would still be pulling little peaces off today if we hadn't spent the extra money. The process took a few days. Here a picture of the wall after all that was done but before we put the final colors on it-
It's kinda hard to see but you can notice the wall paper under all of the stuff that was done.
He chose to go with Oregon Duck colors!
We also replaced the nasty carpet with wood floor.
The pictures are not that good but you get the idea and we also replaced the bottom wall boarder with a new white boarder, but I didn't take a picture of it.