One of his specialties is working with investors - his company has some unique programs exclusive to them, and keeping their loans serviced in house, they don't conform to various overlays that some other lenders have to.

"Non-conforming use" might be some other language you might look into. 

I am currently looking at a 4-plex California, the financials are strong (rare for California) and thw property wIll cashflow after a small downpayment and fIllIng up the main unit wIth a renter.After finding out it fell out of escrow last week I got more details and found that 2 of the 4 units were never permitted and are “non-conforming” units.

@Joshua Matowitz - PMI is on all conforming loans with less than 20% down

However its a level lot, no ledge, only 2 trees to remove, no existing structure to demo, permitting should be easy as the  lot conforms to current zoning laws.

After speaking with an RE lawyer I have learned that these property are non-conforming to current zoning, but require a mult-family permit.

Hey BP Folks,So I am getting ready to sign the PA to get a duplex under contract, which is currently a non conforming property. 

Not Conventional/Conforming products. 

@Jordan Herrmann Sounds like your property is what is called “Legal Non-Conforming”, which means that it is fine the way it is, you can repair and maintain it, but you will not be allowed to expand or add onto the home, due to the commercial zoning designation.

I'm looking to purchase single family house rental that is zone C3 for commercial. What do I need to be aware of in this situation? Should I even touch it?