Hello, we're moving out of our rented place and as moved boxes that have been sitting on the corner of the room for 3 years (!) I discovered a sort of mould patch. I'm guessing it's damp related as it smells a bit musty in the room. It's not proper green mould it's more like a large circle of mottled patches that look almost that grease stains i.e, no colour as such more of a glisten. The walls is beige and the paint is quite cheap so it rubs off.
I need to fix it or the landlord will go ballistic!
Any thoughts?