The counties and states don't have much guidlines for mold mitigation right now so the problem you'll run into with them is just your normal construction permits for demo and replacement.  

My recommendation to them: Spend 12k to demo the building and basically give away the lot to avoid the 30k lien the city would put on it to tear it down + taxes + fines + building violations which would attach to other properties they own. 

Here are some thoughts on it :20% down on the sum of purchase price plus rehab dollars30 year term loan with rates around 5% No prepayment penalty – can flip anytime you want once construction is done and fully inspected by our construction consultantRehab funds controlled by the borrower – no funds ever given direct to a contractorSeller can pay up to 2% of the buyers purchase price as a credit against closing costsLender can increase the rate to offer more cash to pay buyers closing costs so they drop to zero – if flipping the rate doesn’t matter if only making 5 or 6 paymentsYou must use a GC that has to be checked out by the lender and the project approved by the construction consultant – you can do painting or demo but that’s it unless licensed in a tradeBest feature is loan is based on the ARV of the house, not what you paid for it

We put the property under contract and made the contingency set upon getting all required approvals (from the city zoning, BRA design, and ability to get demo permit).  

Perhaps to save on Demo or removal costs strip it out and Give it away to someone for storage space / Shed etc; Possibly if depending on length it might be useful to someone in the construction business. 

For example, they would demo the bathroom - Guest bathroom gets paid %10 or so that friday. 

I just bought a burned out building, which is too expensive to renovate and the city would make me jump through too many hoops to demo. 

ALSO... for some of these properties... if the homes don't get raised and can't meet new requirement and get demoed the land can become green space making it no longer able to be built on.

they don't see a big dumpster full of demo junk and figure out there's a rehab going on, since the flipper took out a regular homeowners policy and ignored the fine print saying they won't cover you if you're doing a major rehab for profit on this place!

They have a demo auction but it seems they need all financial info and deposit.