When I self-managed C Class properties, I would put the requirements for tenancy in the rental listing (3x rent in income, 1-month security deposit, criminal check, etc.), and then when the potential tenants called in, I would speak to them for a few minutes, explain the requirements, get some sort of verbal confirmation on some or all of the requirements, and then invite them to different showing times I had set up.

There are two types of nuisance, criminal nuisance and non-criminal nuisance:""Non-Criminal Nuisance Example; Smoking and the tenant's tobacco smoke drifts into another rental unit, but only if the landlord prohibits smoking in all units."

There was actually a time not too long ago where police would investigate crimes and DAs would prosecute the criminals.

Not to mention, the boyfriend will not qualify as a tenant due to criminal record, insufficient proof income and several other requirements.

Many states require a credit report review  maybe make it like a Lenders license I have U have full fbi criminal and personal financial and credit report.. does not mean you have to be super star but just cant be bad.

Especially now that you've posted your suspicions on a public forum, I'm not an attorney, but I've watched enough Law and Order that I could see there being the possibility of you being charged for "Aiding and Abetting" their crime by not reporting it or "Criminal Facilitation". 

I know most of us have heard horror stories and/or have personal experience about criminals and unsavory characters taking over vacant properties then claiming squatters rights to avert the authorities.

I know most of us have heard horror stories and/or have personal experience about criminals and unsavory characters taking over vacant properties then claiming squatters rights to avert the authorities. 

Good idea except I'm not able to get a realtor's license because I have a criminal record from way back when.

In FL I had a guy who confirmed my criteria and then was upset when I denied for a criminal issue in the background check...because he plead 'no contest'.