It  caused by moisture vapor in the air.

The EPA has a good booklet "Mold, Moisture, and Your Home" that explains how to prevent mold and how to remedy it.  

I'm not sure I need a pet that big to feed) I chatted with the farmer a few more minutes, and he was mid decline speech, when the pig strode slowly and gently around the corner with the six year old boy riding on his back.

But the more gentle route will build relationship, which will serve you better in the long run.People always like to feel some sense of control over their own destiny, so present this as their choice... to stay with you by abiding by your rental terms or to find another place to live.

If the work is not complete then I would reach out to the tenant via text or email with a gentle reminder that rent is due in full.

Could it have been caused by something other than the tenant (i.e. humidity, moisture coming up from the subfloor, etc)?  

Hi all,What do you recommend as the most durable type of paint for a high moisture room such as a steam shower and or sauna? 

Soil has high clay content and it expands and contracts with moisture.

Ask if your  plumber has a moisture meter/detector. 

Check for signs of moisture and enlist the tenant, too.Abnormal use: My abnormal use examples are not just having friends do laundry or washing cars but more like someone's kid leaving a faucet or hose on--all day, day after day...