Due diligence on No w2 tenants

[Mary Jay]

if a prospective tenant is self employed   I can’t ask for w2 verification. So I can ask for the copy of taxes. 

1) what tax form should I ask for ? 1099? 

2) anybody can fake tax form  (fotoshop year 2013 into 2018, etc), should I ask for  the tenant to fill out the 4506 form to request the tax transcripts from the irs myself , right?

How long does it take to get it ? 

Is it an overkill ? 

3 ) can call previous landlords of course 

4) bank account verification ? What else ? 

Thank you!