Hi all!
recently got the keys to my new place and I noticed that these marks are all over every single wall. Looks like water marks but the patterns are so "regular". Before I start renovating, would want to troubleshoot this in case it requires serious work.
Anyone encounter or can diagnose these stains on the walls? My ID and I have scratched the walls and made sure they are not plasters. I have also contacted the previous owner who has encountered the same issue and she repainted the walls. However the marks came back shortly.
