Rural properties are much more difficulty to fill only because you are drawing from a much smaller pool of tenants.

Unfortunately, technology does make it easy to forge things such as an ID, social security card or pay stubs.

I'm 30 years old, have $79,000 in investments + $7000 in liquid cash, and want to build up a passive income that pays for a mortgage on a qualitative ($250,000) home, lets me drive a car I'm not embarrassed to drive ($45,000), and gives me the security knowing that if I ever have difficulty finding a job that pays what I get paid now, I'll never have to worry. 

Start with the county website: http://jacksoncountyor.org/Departments/Information-Technology/Property-Data-Online

Clearly buying 3 houses will give you the best long term investment however many of encounter problems and difficulties where we may need to liquidate our investments.

We have been using Trello forever, but are looking in to Process Street software because of their awesome checklist technology.

Any difficulties or things to consider with this strategy?  

If rents move to market I would be positive $200-300.How difficult is it to evict tennants and/or raise rents to market?

Keeping yourself healthy and strong doubles in difficulty every ten years, so build a good foundation while it is easy.

As internet technology is a business I have and am keenly interested in what others are doing.