We have been having issues with the people who live below us (we live in a co-op)...our bathroom was leaking into theirs and since it was not an issue inside the walls the building will not pay for any of the damage to their apt.

We have fixed the leak and now they are hounding us to get their bathroom fixed. They claim that because of the leak mold has grown and is growing on their walls which needs to be removed before any of the walls are fixed.

Does anyone know around how much it costs to remove mold from a wall? I don't even know who to contact for such a thing.

This whole situation is such a nightmare.