This increases the value of any property as well as making it easier to refinance or leverage to buy additional properties.

Or is there an easier way?

Zillow has already stated that its target is to net just $3-$5k per deal, and by volume, create an additional $1B in revenue.

And I'd target deals that the seller will finance, OR, get private money (not hard-money) and give them say, 6--8% interest only for x (maybe 5) years. 

Sounds like you're targeting Kean University.

It could be a lot easier to get 1 loan rather than 6 mortgages and you get the added benefit of having to pay expenses and management on only a single property rather than multiple spread across a wide area.

Here’s my quick look at the BRRRR calculation:$220,000 ARV x 70% (All-in Costs Target) & Refi LTV = $154,000- $35,000 Rehab estimate = $119,000- Closing Costs - Holding Costs = Maximum Allowable Offer (MAO) or Purchase price Your $165K Purchase price is already over the 70% (without Rehab, Closing, or Holding Costs).  

Assuming these are non-profit orgs that are not restricted to religious organizations or targeting protected-classes, is this actually legal?

Vehicles are much easier to foreclose and reposes than a house so they will take them first.

In the Dallas area, it would depend on what class of property you are looking for and what your acquisition parameters - financial targets - are.