I'm not sure you should feel confident about the return on your equity if there is no cash-flow.

Has anyone identified a creative way to get residents of properties purchased at foreclosure to leave on their own without having to pay Cash for Keys or bearing the cost of evictions?

If the intent is to flip it, there are two ways people buy houses 1. with borrowed money 2. with their own cash.

What type of financing or cash are you using to purchase?

@Rami Latif - they might extend it if you need more time to come up with the cash

High cash flow properties right now are often going to be in lower appreciation markets and harder rent markets.

And then using the net cash to go wherever they want every year on vacation. 

You could preform a cash out refinance, the lender would use some of the cash out proceeds to pay off the back taxes at the closing.  

Run the common rent comps and compare that to your PITI and overall costs to analyze cash flow.

Then we stayed in our fixer-upper, used HELOC to buy investment property cash, then get a cash-out mortgage and pay back HELOC once rented out with rental history to qualify, and do it again.