I tried negotiating but they didn't approve, so I walked away from the deal.

@Sergio Roman II what’s plan B if bank doesn’t approve first heloc?

If the deal can be scrutinized and approved by a few lenders you’re likely in a solid position.

If they don't, they'll probably still want to see photos of the place before approving it. 

The person to do that is a HUD approved FHA 203k Consultant.

How do they view applications to change zoning (tendency to DENY vs consider APPROVAL?).  

So take what I say with a grain of salt.The first thought that occurred to me is to double-triple-check that the property's conversion from a duplex to a triplex was approved by city or county inspectors, and recorded with the recorder's office. 

I have about 70-100k cash that I can use and got a pre approval for 200k ,based on the parameters given to the home loan officer.  

The judge then approved removal of the C&Rs for almost all the remainder of properties in the subdivision.

Insulation is different to day, where R-50 was approved, some place are now requiring R-60.