Cambond via Amazon offers its Cambond Outdoor Water Resistant Bluetooth Speaker for $26.99. Coupon code "VYAMRQ84" cuts that to $20.99. Plus, Prime members bag free shipping. (Non-members can spend $49 or more to qualify for free shipping; otherwise, it costs an extra $6.59.) That's $29 off and the lowest total price we could find. It features a Bluetooth range of up to 33 feet and built-in microphone.