Most are just baseless claims like my kid has asthma because of mildew in the bathroom that I haven't cleaned since I moved in.

Sounds fishy and sounds like they don't have proper documentation for what you are claiming.

In Indiana it's supposedly a "90 hour" course. Yet I'm over 1/3rd of the way done in under 15 hours. I don't know if I read faster than they provide time for? Or if I just find it easier so far because of my real worl...

(The WC carrier will certainly subrogate (go after you) for that claim). 

Are you receiving your rent rolls in its correct amount or is the PM claiming its going to repairs so its always short.

Customer service is important, too.

Added features in a property can identify you, it can be as simple as a custom touch on kitchen cabinets, a key stone arrangement outside, a custom door knocker, an igraved mantel or a decorative feature in landscaping. 

He owns his own company and it sounds like the company is pretty new although he claims to have a large contract with one of the bigger contractors.  

Clearly you don't want to go into it with the plan to learn the business then steal all of their customers but knowing the current owner's end game would be important from the beginning.

In my "day" job, I have 10,000 customers billed for services on a monthly basis.