I had occasion to meet the family and they have been known for their multi-million dollar gifts to charities and public causes.The house was built in the 1950's. 

Instead of trying to figure out what your money is worth in the future, NPV allows you to figure out what future money would be worth today.Here's another way to think about it...In real estate, there are many occasions where you have the opportunity to pay a fixed amount today for a stream of income later. 

@Grant Huggins The IRS language is as follows:  If a tax exempt entity engages in a trade or business on a regular or repeated basis, then UBIT applies.A single flip on rare occasion mixed into a portfolio of largely passive investments would not "likely" be subject to UBTI, with the caveat that the IRS has the final determination should they choose to take a closer look.  

@Ron Averill I spoke with the head of the community development department on several occasions to make sure I wasn't wasting my time with this property. 

The individuals schedule has not permitted that on this particular occasion.

@Ned Carey I've been making my rounds through the area on several occasions but theres only so much a drive by can give me.

Yes, I do [on occasion] cherry pick some for my own portfolio for the occasional flip.  

If the $800K is sitting in cash and not equity, that means you need to have an additional $800K in debt, at just 4-5% interest per year, you are talking about those cash reserves costing you $30K-$40K per year ... it is much better from a financial standpoint to keep more modest cash reserves and maintain lines of credit to draw down on for special occasions.

I have also lived in the US on two separate occasions before, one time where i was a cross country tour guide which took me to 39 states, so i know US history and geography better than most normal americans do as it was my job, and another time when i completed my Masters Degree in Real Estate investment at the University of North Carolina.

I recall seeing mortgage liens missed on title commitments on at least 3-4 occasions when I was selling.