There are people in here who could have used a handful of that cash and turned it into a lot of money.

First: Define “good.”Second: Why would any owner want to leave money on the table, especially money sufficient enough to make a market deal a “good” deal for the buyer?

If people have less money they'll travel less.

However, it looks like to the left it connects to another room (maybe the living or dining room) if so, I would see if it was load bearing and maybe take down that wall and make it a little more open, probably put an island where that is.For the outside, it mostly looks like it needs a new paint job, fresh grass, and some pressure washing. 

What I'm hung up on is how to make a deal work so that it produces a satisfactory rate of return for the money partner.

Business/money has ruined many relationships:(

Out of money and options, he licks his wounds and lets it go for back taxes. 

@Liliana Bennett most HOA boards are composed of the actual homeowners.Just like there are many DIY owners here on BP, trying to pinch every penny, there are HOA Boards trying to do the same.Guessing your HOA Board members have specifically taken many possible tasks away from the PMC in an effort to save money.

I'd say the Bigger Pockets forums are one of the best places to explore how to put your money to work in RE. 

In the old days this was known as “flash money”.