I live in an apartment and techincally, I am not supposed to do anything with my walls. It's all white, except for one wall that divides the living room and galley kitchen.. that wall is red.
Mostly painted walls. Some walls have paper and some have material. I can change material faster and cheaper than paint. I am moody and like change to up my mood. After that I decorate with cats
And since it's a personality trait of mine to enjoy starting things and to hate finishing things, my bedroom looks like a Battenberg - part original yellow and part new brown.
I can paint, and do a decent enough job, but don't like ladders so it ain't easy. Loathe wallpapering, end up with it on me instead of the walls. also not fussed about the look of it. I'm afraid to start here because there are layers and layers of wallpaper to be removed and under that, old oil based paint, complete with lead
Painted; it allows me more freedom when it comes to the wall art I want to decorate.
That being said, I think it would be beautiful to have a really pretty accent wall with a lovely wallpaper! (Or even have it put into long frames, so it's less-permanent and easy to change up!)
I have painted walls with chair rails around the main rooms. Different paint above and below. I LOVE to paint and did it all myself a few years back. One bathroom still has wallpaper which is on the list of "To Do's" to take down and repaint eggshell.
Everything is painted right now. We used to have wallpaper in the computer room and in the bathroom. When we stripped the wallpaper and painted the bathroom, we used a painting techinique that makes the walls look like they were papered. It's really nice. But when we get tired of it, we can just paint over it.