Painting over wallpaper

[Foreverblowingbubbles18]

Has anyone done this and has any pictures?
My mum wants to paint my old room for my baby but the walls are so bad, plastering is probably too costly so wanted to see if anyone has painted over wallpaper and what it's like. Just normal paper not textured that you'd usually paint anyway.

No pictures but in our last house we put up lining paper so we could paint it as the walls were awful. It made it pretty smooth, just a slight bump here and there where there had once been a dado rail but a lot better than just painting the walls.

We used an undercoat wallpaper covering paint from B and Q and painted over the wallpaper. Then two coats of normal paint. Looks great.

We painted over ours, I will post a pic when I can.