Linksys offers the refurbished Linksys Smart 802.11ac Wireless Dual-Band Router for $54.99 with free shipping. That's $64 under our refurb mention from last June and the lowest price we've seen for this router in any condition. (It's also $114 below the best price we could find for a new one today.) It's backwards compatible with 802.11ac networks and features a 1.2GHz dual-core processor, speeds of up to 1.3Gbps, four Gigabit Ethernet ports, Gigabit WAN port, USB 3.0 port, and LED status indicators.
Note: A 90-day Linksys warranty applies.