Lots of folks running ventfree gas fireplaces in the winter now. Really causes lots of water in the air with no exhaust....if they were in home before warm weather.

+1.

A few years ago, every apartment and condominium complex was worried about mold, as attorneys had identified mold as the next big thing for lawsuits.
Every apartment complex was expecting to get sued into bankruptcy until the whole thing fizzled because mold is so easy to eradicate.