When looking for black mold, it’s best to start where you know there’s been water damage or condensation. You may notice discolored patches on the walls, ceiling or floor. You may also see cotton-like growths on any of those places or even on your own furniture. But keep in mind that sometimes mold will be inside the walls and not immediately obvious, so it’s wise not to discount the other signs.

Here are a few common signs of black mold in a home:
https://www.moldremovalexpress.com/4-signs-that-your-home-has-black-mold/