B-1 83 said:

You've been lucky. I am the pseudo landlord for an absentee owner. I am paid a small bit for watching over this house. Twice in the past the damages to the house exceeded the deposit. This bunch as been constantly late (paid late fees) and written hot checks. They have also lied about number of pets and shirked the extra deposit. The law is a beotch when dealing with such situations, and "harassment" is easily claimed.
I've heard of some cases where renters broke through the foundation in the house and dug networks of tunnels underneath the house. Then, once the house was full of dirt from all the tunnels, they moved out. I never figured out why someone would do that.

There are more and more reports of people who move into a house with no intention of ever paying rent. In some cases, they rent the house and in other cases they just move in. Some seem to think that if they do this, the house is theirs because of adverse possession. Imagine going on vacation to find someone living in, and tearing up, your home.