I would do wallpaper first, then the hanger won’t have to cut around mirror/sconces and try to match the pattern, which is a waste.

Judy, thank you! That was my thinking, too, but I’ve never done wallpaper. I’ll get to work on coordinating that. I appreciate your help!

How is it a waste? It's the same amount of paper either way. Is the mirror being hung on the wall with a hanger, or is it being adhered to the wall with adhesive?

We will use anchors & hangers for the mirror. It’s a large floor mirror from Crate & Barrel, so it’s got some heft to it.

If you don't currently have lights where you're going to have the sconces mounted, have the electrician place the electrical in the wall before the wallpaper is installed. They'll be made safe while the rest of the work is being done.

The GC’s paper hanger (not yours, in the middle of everything) should do it after the rough electrical, and before the vanity or finish electrical is installed. Right about the time the tile is being done, but not with them stepping on each other. Which is why the GC should hire and schedule this, and be responsible for this.