Due Diligence Buying From Wholesalers

All, 

I am looking at taking on a BRRRR project but have been having difficulty finding a deal that pencils out. I have agents on my team looking as well as myself scouring MLS daily. I have been getting regular deals from wholesalers that for the most part I disregarded as I see them as quite risky. I am starting to change my tune a bit.

I am looking for due diligence advice from buyers who have closed on deals with wholesalers. My agent and PM would review the deals as well to ensure my numbers and neighborhood eval is correct. I have heard stories about zoning issues, outstanding liens and such, etc. Is there a way to confirm this stuff before I close on the deal?

Please let me know any tips. Thanks!