There are some recommendations that I wasn't aware existed to creatively finance or reduce the cost of this 4-plex.  

I would suggest that you keep in touch by telephone or passing by every month to six weeks. you are attempting to establish rapport and some kind of relationship so that when he decides to reduce price or comes to understand that you are closer to the market than he was then he turns to you over those he might have spoken to in the interim.

This keeps the cost down and reduces the calls. 

Since I have been playing for a while and the industry is getting smaller due to regulations which reduces the traffic and the number of recreational players (which makes the game less profitable) I think is the moment to start transitioning to Real Estate.I am literally devorating everything in BP, just bought the 2 books of Brandon Turner (hey Brundon if you read this just let you know that I love the way you explain and the methods of teaching you follow, I really find them effective for newbies like me) so I will be trying to educate myself in RE as much as I can in order to be succesful in the future.If there is someone out there who is also starting in RE, in spanish market and want to connect me to talk about whatever or just for future networking, dont hesitate to do it!

What are the key market characteristics that I need to analyze to reduce the chances of owning property in a town that is dying fast?

Check out my first blog post in my profile, I actually was able to reduce my closing costs several thousand by doing this.

If you're not licensed, you can likely still cut some of the expenses by working an agreement with your realtor to receive full commission on the purchase of the property and a reduced fee on the flip (since your agent would get 2 commissions on one property, it's not unreasonable to ask them to take a small reduction on the back end of each one. 

If the majority are owner occupied, the board could change the bylaws to prevent or reduce future rentals.

I would even put some Section 8 tenants in this category, particularly the older people who have been on the program for years.D Class: People who have only ever lived in public housing or with family.

Check their names in public records (court, etc.) and social media to find out more about them.