Cafago offers the KKmoon 720p 4-Channel 4-Camera Infrared DVR Security System for $159.79. (Make sure the US warehouse is selected.) Coupon code "S1003USG" cuts that to $109.94. With free shipping, that's $136 off list and the lowest total price we could find. It features four waterproof 720p IP cameras, night vision with up to a 100-foot range, up to a 3TB SATA hard drive capacity, HDMI, USB, and mobile connectivity.

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