The issue was a person sold their home subject 2 and the person who bought it stopped paying.

Was that person me or another person as that sounds like something I have been telling people? 

I personally would fix the 3 windows and maybe consider cutting the rent a little more to gather more interest. 

People like to rent from a person not a 'brand', it's more personal.

I personally haven't sent postcards, I've had good luck with PPC and Video ads. 

The interest rate on a HELOC or Heloan may be better than the personal loan. 

And what if the one person you didn't check has a criminal background, has collections, and more?

Personally, I would not keep a rental that is not expected to cash flow. 

There are many here in my local area and your area is likely to have the same type of meetings.Most of the deals that I fund are by meeting investors in person at these groups and creating strong relationships. 

My personal preference for a buy and hold would be an already established area (or an area that's still gentrifying, but has already seen significant progress).