Yeah the damp / mold smell is a no-go for me. I rented a place in a popular east coast resort town for the family, and the first thing that hit me was the damp and moldy smell of an existing or recent moisture problem. Not an AirBnB, but some hosts/rental places just don't care about guest comfort.

It cast a pall over the whole stay. It was hard for me to be comfortable, I could not imagine a long-term stay. The kids didn't mind though, and luckily we weren't worse off for it.