Newegg offers the Trendnet AC750 Dual-Band 802.11ac Wireless Router for $9.99 with free shipping. (Amazon charges $1 more.) That's tied with our March mention as the best price we've seen, and it's a low by $4. It features a maximum speed of 733Mbps (433 Mbps AC + 300 Mbps N), dual-band support, and four Ethernet ports.
Dell Small Business offers the Trendnet AC1900 Dual Band 802.11ac Wireless Gigabit Router for $49.99 with free shipping. That's the lowest price we could find by $18 and the best deal we've seen. It features dual-band support, four Gigabit Ethernet ports, the ability to create an isolated guest network, and USB. Deal ends July 2.