VMInnovations via eBay offers the refurbished Ninja Professional 1,000-watt Blender, model no. BL610, for $49.99 with free shipping. That's $5 under our April mention of a refurb and tied as the lowest total price we've seen. (It's also $29 under the best price we could find for a new one.) It includes a 72-oz. jar.
A 90-day warranty applies, but it is unclear who backs it.