I bought an old house and renovating one room at a time. I did demo on a bathroom which looks like it was done in the last 15 years.

Paint all over the walls is chipping. It almost seems like they put new drywall up and just painted it with no primer. I’m going to scrape off all chipping paint and go over everything with a sanding pole and use a good primer before repainting, but is there anything else I can do to prevent it from happening again like a certain primer etc? Or does my plan seem sufficient? Thanks