Since Marriott now has a formula for dynamic award pricing, I wonder if they'll eventually offer a way to use FNA at Homes & Villas. Maybe if they can't equate them to free nights, they could be redeemed as a small price reduction similar to a cash & points copay. With the growing popularity of rentals like vrbo and airbnb, this would be an innovative loyalty perk those competitors don't offer. I can imagine Chase and Amex might like to market this to acquire new card members.