NeweggFlash offers the refurbished Linksys AC1200 802.11ac Wireless Dual-Band MAX Range Extender, model no. RE6500, for $34.99 with free shipping. That's the best deal we could find for a refurb today by $10 and the lowest total price we've seen for it in any condition. (It's also $45 under the cost of a new one.) It simultaneously extends ranges for 2.4GHz and 5GHz bands up to 10,000 sq. ft. and features four Gigabit Ethernet ports, a 3.5mm audio jack, and support for up to 128-bit encryption. Deal ends October 17.
Note: A 90-day warranty applies, but it's unclear who backs it.