The 3 options outlined above are for the CASH program as of August 2017.
I'm with you on the recourse, I wish it weren't part of the program but it comes down to math. After a lengthy discussion with the head of the CASH program it became clear to me why they have to make it a recourse deal. In order for 21st to cover their losses on defaults if they did a non-recourse deal they would need to charge 16% interest. However, Dodd-Frank makes this illegal (They are capped out at something in the 10-11% range). That means they need to find another mechanism to cover the losses and recourse is what they came up with. It is basically that 5-6% interest rate spread that park-owners are subsidizing when they co-sign on these homes.
As far as impact that CASH homes have on park liquidity, we recently sold a park with about 10 CASH homes in it. We were upfront in our marketing that the sale was contingent on buyer taking over responsibility for CASH homes in the event of a default by transferring them out of our name and into theirs. This request seemed to have no impact on the transaction - we had multiple offers at or near our list price.
It's not a perfect program, but used wisely CASH can be a nice tool to your infilling toolbox.