They have the knowledge, but still only about 12 people do most of the deals. Unfortunately, I don't like to say it, but most people are lazy. All of this is from just one, two, or three deals a year. The worst first. It is work, just like any other business.
Some tenants do tear things up.
However, if you screen properly and set policies and procedures, you can minimize your headaches and losses. Most landlords run their business like a bad hobby. In six years of being a landlord, I've never had an emergency. If there has been one, the police or fire department takes care of it. We have our set policies and procedures and we enforce them.