I know I bang on about the advantages of soap as a cleaner, but for marks on walls I really do find that bar soap (uncoloured) on a microfibre cloth works as well as, and is gentler than, a Magic Eraser.
The staircase leading up to our studio is narrow and rather awkward and I used to see guests being very nervous about banging their suitcases into the walls and making a mark or gouge. It took lots of touching-up of marks to make me realise that it was actually better to leave the marks, so that now I can say to guests “Don’t worry about damaging the wall with your case”! and repaint that bit just once a year or so. I realise that you can’t do that in a bedroom, of course!