The sellers lived in the basement and rented the upper two floors. These people had a bedroom with no egress window, and if a fire were to occur outside their bedroom, they would likely perish or be burned. But that's their business. I told the buyer NOT to sleep in the basement until an egress window is installed. Quite a big job though.
I also found wet drywall on several walls indicating a moisture issue is present (see picture).
These walls will need to be opened to see whats going on so the water issues can be addressed. This is quite common in finished basements, so if you like mold, finished your basement with drywall these these people did.
Actually, I recommend a qualified basement water proofing company evaluate these areas and make their recommendations. If water is entering from the exterior, that these areas will likely need to be address from the exterior.
This may require removing concrete patios so you can dig along the foundation walls. So it is not always an easy fix. Painting your foundation walls in the basement with special waterproofing paint is a complete waste of time. Address these issues from the exterior with properly licensed and established contractors.