Iextremeofficial via Amazon offers the Holan 12-LED Waterproof Solar Motion Sensor Light 2-Pack for $18.59. Coupon code "RW6B3MP5" cuts that to $12.08. Plus, Prime members grab free shipping. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping costs $6.90.) That's $18 off and the lowest total price we could find. They detect motion from up to 26 feet away and feature auto on/off and a waterproof rating of IPX-4.