Another factor is that while everything is going well, it may be perceived to be cheaper to self manage.  

Another factor is that they are trying to stay in the same school district though I know that's not my responsibility, I know it can be hard to find a decent priced place in this area.I understand that neither of these might be considered a great candidate as I've read a lot about what minimum requirements should be but I believe that both of these would be good after running all the background checks.  

Income is from SSI except for dad who makes $6000 a year working as a "D-boner" (I'm guessing deboner) in a local chicken factory plus (mom claims) gets a VA disability but she can't find the paperwork to prove this.

They're saying they're not obligated to pay for April or May because the 90 day notice period was meant to be for them not renewing, not for me selling the building.It's in Massachusetts and, according to some Googling, I can keep the safety deposit for non-payment of rent but the complicating factor is that the tenant is 1) a minority 2) a lawyer 3) a town selectman. 

The Cheesecake Factory Tells Landlords Across the Country It Won’t Be Able to Pay Rent on April 1.

This week alone I've had an HVAC leak (2yr old unit, defective factory part), a toilet shut off valve washer disintegrate and clog line, and an above range microwave die. 

If your strategy is to buy rent and sell in three to five years then appreciation would be a very important factor.  I

So, you need to look at how much rent they are actually getting - and don't trust Zillow or one of those online estimators.Also, see if there is any other reason there are vacancies, like jobs leaving town, factories closing, that kind of thing. 

I bought from a factory all new homes energy efficient.

We used to have factories and mills that provided those jobs maybe one day we can bring those back.The average deal now for a C+/B- multi-famly building in my area are selling for a 5-5.5 Cap.