A lot of them will have criminal backgrounds.

I also check the court records (civil, criminal & traffic) myself, just in case something was missed.  

I did self manage and self lease, so I screened all tenants looking for no evictions, no criminal background, good landlord references, long term tenancy, etc.  

We require any tenant 18 or older to qualify for whole rent on their own unless they are a legal dependent (spouse, college student, dependent parent, etc) of applicant, even then must pass criminal background check.

For example, I mention that every adult must pay a $30 application fee, pass my credit/criminal background, make a combined income of 3x the rent, and whether or not the property accepts pets.

I have transacted at least 5000 properties as a flipper developer and lender and I have had one instance of this. were someone recorded a mortgage 5 minutes before my loan went on record so when I got my title policy I was in second instead of first made a claim to my title insurer and they rectified it quickly and went after the bad guy criminally. 

The trend in larger cities has been for less police and more leniency with criminals.

I think this is proven that even in ponzi criminal case, if asset has good valuation and the law is being done properly, we will get our money back as investor.

For example a tenant has to meet certain qualifications to be able to rent your property: income, credit score, evictions, rental history, criminal history, etc.

PS Rochester and Buffalo were ground zero for much of this stuff also there were groups buying those homes for 10k packaging them up and selling them for 80k to investors from England. the city / state finally cracked down on that and there was some folks that got in trouble on the criminal side of it.. you can google it.. wont mention names but you can find it if you dig deep enoughBut this is nothing new.. buying hood rates for pennies and selling them for dollars to foreigners and unsuspecting out of state folks.