Decorators are often asked to paint a room (walls and ceilings) but leave the existing wallpapered wall in place. This is often done when the wallpaper is a feature wall or when the homeowner is attached to the wallpaper and wants to preserve it.
However, it is true that painting a room with an already wallpapered wall can be a more difficult and time-consuming task than painting a room with plain walls. This is because the decorator will have to take extra care to protect the wallpaper from paint splashes and damage.
I would recommend decorating the walls simply using
best peel and stick wallpaper. Firstly, they are easy to apply to the walls, and secondly, they are cheap. This is ideal.