I am an agent/investor born and raised here in San Antonio.

So, I started buying between 2009-2012, which was a few years earlier than I wanted (I was hoping my wife would be back to work after raising the kids through kinder and we'd have two incomes). 

Posting the links to each on Facebook pages raises the visibility as well. 

Assuming I decided to go ahead and raise the rent at that point, I'd let them know and I'd give them some reasons why. 

The previous owner never raised rents, so they are ~$600+ under market rent.

I can see this principal applying more broadly to AP subject you are raising, but also as the STR legal landscape develops (and the end game there seems to be eventually heading towards a more unified policy and even constitutional argument in front of the Supreme Court, in my opinion) - this may apply very readily to a sound legal strategy for STR protection? 

I just purchased a duplex about 3 months ago and recently had the lower tenant move out because I raised rent higher than she could afford. 

I took a similar path when starting in RE, but I was born and raised here in AZ.

One group that comes to mind raised $140mm from, if I recall correctly, about 150 investors.  

I would suggest starting lower for "early birds" and as you get closer to completion raise the rents to market value.