Amazon has the TP-Link AC750 Dual Band WiFi Range Extender (RE220) for $18 - $4 off coupon clip (coupon applied to one item per order at checkout) = $14- with free shipping on $25+ or with Prime. List price: $35. Extend Wi-Fi Coverage - Boost Internet Wi-Fi Coverage up to 1200 Sq.ft and Connects up to 20 devices. Features transfer speeds up to 750Mbps, Ethernet port. #1 Best Seller in Repeaters.
Has good Amazon Reviews.