(Happy to give you my honest opinion on the deal if you'd like to share details via PM.)There may be some heartburn in the short-term, but what's bad for the Energy industry (cheap oil) is good for the rest of the economy (cheap gas).

For the most part this just means that 3 out of 5 Americans will be renting for the rest of their lives.

Leave the rent where it is, the rest of your requirements are all reasonable.

With a reno as you have stated - New roof, windows, siding, HVAC, insulation, etc - you have a minimum of $50K assuming you do some work and contract the rest and that is not going high end. 

At the same time submit the rest of the drawings for permit that may take more time.

The bank decided at the last minute that they would only forgive a portion of the debt and wanted to do a short sale on the rest of what was owed. 

I'm working on having 75K down (HELOC from my primary) and I am going to ask him to owner finance the rest.

As for the rest, no.  

If he owes $100k on it, and needs to pay that off to reset his VA entitlement, he would need a $100k (plus closing and settlement costs) down payment just to walk away from closing breaking even and seller finance the rest. 

Just a quick thought, don't know if the numbers would work but say you were able to get a hard money loan for $25,000 to do the repairs and pay back taxes (or even pay some of the taxes and try to work out a plan with the town to repay the rest over time going forward).