I need to build a diverse and robust cash buyers list so that I can finally close on my first deal.

Its fairly robust and free for a single unit. 

You'll want someone who has some familiarity with managing Airbnb's specifically and can help you strategize static or dynamic pricing to better compete with neighboring properties to keep occupancy up as well as a manager who has a dependable cleaning company who is familiar with turning around a rental after the guests depart.

I know there’s so much discussion about purchasing in lively busy growing areas that I feel conditioned to not consider markets that aren’t as robust.

Incidentally, I've written about how to get around the due-on-sale clause you'll find in most mortgages with a few strategic moves here on BP as well.

Biased opinion, but... the money you will pay your CPA you will receive back many times over when you file your taxes and, more importantly, when you get the strategic advice that will help you plan ahead and make wise financial decisions.

Be patient and strategic.

My personal recommendation is to strategize with risk mitigation in mind, not capitalize on potential market changes.

It might be time for your parents to strategically downsize before the trouble begins. 

Everyone is doing the exact same thing, using the same letters, postcards, or whatever but the way I'm doing things is a little more strategic.