Beyond immediate safety concerns, the long-term financial implications, including taxes, are a pressing issue for those impacted by the disaster.

google "all inclusive Deed of Trust" fantastic CA document we used all the way back in the early 80s If I'm not mistaken though a wrap would require the 2nd buyer to also agree to financing terms; which would be the same as me (the 1st buyer). 

The appraisal came in at $245K, but they are only loaning me 70% of the ARV.

If you are going to be an owner-occupant, want a low down payment, and are planning to do a renovation, the FHA 203k and Fannie May Homestyle loans are your best optionsHow do you know the property is currently upside down on the mortgage? 

That is tight leverage for an investment 2nd position loan.A private investor might be willing to do it, it's not going to be cheap at all & will be short-term money & will not be a line of credit to take out at your liking.What is your rate on the 1st?

People reinstate the loans and do loan modifications all the time.

A 1031 exchange will allow you to sell your building and use the proceeds to invest in a small multi family and/or medium term rentals.

Negotiation tip #47, make it as simple as possible for the other party to accept your terms.

I know it’s going to take a lot of digging and possibly building my own pipeline for off-market leads to make this strategy viable long-term.

If you’re leading it to a company be sure to have in your lease explicit information about who is responsible for what in terms of maintenance.