I've found a lot of random acquaintances who have gotten into REI so it's more common than you think. 

My random questions are:1) How is building class really determined -- aside from the obvious?

If you think some random home in some random city is going to out earn an index fund or Apple or Goog stock ...think again as one was 100% designed to be lived in and the other was 100% designed for investors returns. 

I am not there but the owner, four of my coworkers and about forty random people are there hanging out and talking shop.

I know I'm a couple days late to this thread but had a couple thoughts to share.The rapid price appreciation in the neighborhoods @Patrick Young described isn't random, it's what happens when an intown neighborhood transitions from being primarily rentals to being primarily owner-occupied.  

I have looked into turnkey options, but am wary of just random houses in random neighborhoods.  

I didn't plan on mass email people at random because as you said, that personal connection is important.

You are likely aware, but the random reader may not know this.http://www.irafinancialgroup.com/solo401kassetprot...

It takes more than a random email or text to get sellers convinced that you are the realtor or investor to work with.Bigger Pockets user please share your experiences with cold calling in the reply section. 

It took numerous phone calls from my agent and myself to random people in some outsourced office halfway across the country and weeks of stress to finally get the loan closed (and only because the seller agreed to an extension at the last minute).