I'd venture to guess your tenant is a criminal or drug addict of some sort.There's some truth in your thought but he's actually a really nice hard working young man. 

The type of rooms students would need or skilled temporary workers, not drug addicts and alcoholics. 

I feel like I've dealt with every time crazy situation there is here in Chicago with squatters, evictions, drug dealers, etc., and I still love Cook County because I have a solid team and underwrite deals properly.I think @Paul De Luca nailed it on the head, though - it seems like you are quite risk-adverse, so maybe given your risk tolerance, it's not the best idea, but if it were me, I would not think twice about it, and find a rock start property manager who knows exactly how to vet tenants.

Non paying tenants(as a newbie I did no screening), dead tenants, Silly fines from the city for nothing, attempted robberies where I ended up with the cops pulled guns on me. 30 recently released convicts as neighbors for a while, a jacked up 7' tall transvestite call girl/drug dealer was my least favorite neighbor.

This self claimed "Drug Addict to CEO" doesn't pass the sniff test in my opinion.

Like deferred maintenance, (bad roof, worn out water heater/AC Unit, warped flooring, water damage) etc, unpaid utilities,  unpaid taxes, a second loan, unpaid HOA fees, a bad pool, bad reputation, sometimes squatters, sometimes they were drug houses, and so on.

Every adult should be fully screened to ensure you aren't renting to a violent criminal, drug dealer, etc.

I hear a few have made money with him, but many have lost.I heard Joey was arrested for drugs, but haven’t heard much else.

Crime and drugs still an issue, but getting quality tenants has not been a challenge... so far so good.

You have the usual causes like drugs/alcohol problems, mental illness and then you have the working poor who remain homeless.