another property to the portfolio, and a continued relationship with a live long client Lessons learned?

Hopefully, not an expensive tenant or Fair Housing lawsuit.100% of what @Travis Biziorek states is true, but he left out a key fact - he lived in the Detroit area when he started investing here, so was able to self-manage and meet everyone he had to hire face-to-face.

The past tenant was a hoarder and the apartment has not been lived in or touched since 1999 (26 years)! 

That was when I had enough, and decided to end the lease.He has been living month-to-month for some time now. 

I lived in Austin for a couple years.

When I tried to get it when my side of the family found out and tried tp take over reverse mortgage payments to bank because she had died it was to late so they sold the house to Hud and then other reverse mortgage companies but a relative still lives there so they can't kick them out.

another property to the portfolio, and a continued relationship with a live long client

I'm a Realtor with a couple properties listed in Boise, ID and a neighboring town for my investor/client that are currently rented as co-living or rent-by-the-room and getting killer income. (7.3% - 9.5% Cap rate) So far, every inquiry has been baffled by the concept of co-living or rent-by-the-room and immediately ask if they're being run as a halfway-house (which they are not).

Right now I have two properties live.

A duplex where I live and the duplex that was offered to me.