I rented a reservation for rent here on DIS. about 3 days ahead of time. It really just lucked out that air was cheap enough. I paid pennies on the dollar. Maybe 4-5$ a point. SSR in early Dec, maybe 3 yrs ago.
I would try other places 1st. Friends, family, ebay, craigslist ect. If the points are not expiring try renting the points too.