Ebay offers Refurbished NETGEAR C6300-100NAR Dual-Band AC1750 Router Cable Modem for $82.99 (orig. $199.99) with free shipping.

Product Description:
Grab the highest cable speed currently available and AC WiFi in one smoking fast device. The AC1750 WiFi router and integrated DOCSIS 3.0 cable modem—with up to 680 Mbps—combine to deliver the ultimate in HD streaming, online gaming perfomance, multi-device connectivity, and works with all major cable ISPs.
Features:

• Compatible with Xfinity from Comcast, Spectrum, Cox, CableONE & more
• Three-in-one DOCSIS 3.0 Cable Modem + AC1750 WiFi Router+ 4 Gigabit Wired Switch
• Up to 680Mbps modem speed and Dual-Band AC1750 (2.4GHz & 5GHz) WiFi speed. 16x4 channel bonding/ Approved for plans up to 300 Mbps
• DOCSIS 3.0 unleashes 16x faster download speeds than DOCSIS 2.0
• Ideal for streaming HD videos, faster downloads, and high-speed online gaming
• Works with Cable Internet Providers like XFINITY from Comcast, Cox, Cablevision and more (not compatible with Cable bundled voice services)

Thanks Lionking