I'm assuming you've done what you can online by looking up the parcel info in your county parcel viewer, online searching parcel # and address?

Also in a quick look on Redfin I believe that I found the property you are considering (I don't want to reveal the address on here) and it is listed as a hot home likely to sell soon, so I think it may be unlikely you will get that steep of a discount.

My pitch would be something to the effect of "I'm a real estate investor, and I'm interested in buying your house as is for cash. 

If I am reading it correctly this would reduce taxable income significantly but still not to the effect of a step up basis in an inheritance scenario.     

I would of course immediately call that lender directly (if I weren't myself a lender then I'd have my agent make this call; good agents have strong "the lender is throwing spaghetti at the wall" BS detectors) and drill down on how many 100% CLTV commercial loans said lender has done in the last couple years, and ask for property addresses so I (or my agent) could validate from public records (which takes ~5 seconds for a RE agent or lender to look up).

As long as your mailing address on your bills is that address and you claim that address on property taxes for your homeowner exemption (may vary from state to state), it's considered your primary residence.

.- At this point I don't know what more we can do to address the perceived mold issue because we've complied with every recommendation from a licensed abatement company and testing agency.

@Isaac Geller When you say "Grand Street" as the address, I'm assuming you're referring to Jersey City.

I've gotten the property address and it's a listing from the MLS.

I found the deal by driving for dollars, taking down all the addresses of the multi-family buildings in the town, going to the local registry office to pull titles, and cold calling all of the multi-family owners.