GoPro through ebay has their Refurbished GoPro HERO4 Black 4K Action Cam, model no. CHDHX401, for $234.99 with Free Shipping for a limited time. It comes factory sealed and with a 1-year GoPro warranty. Limited to 5 per customer.
The GoPro HERO4 Black Action Camera features 4K high-definition video recording at high frame rates, ultrawide-angle glass lens, QuikCapture, built-in microphone, built-in Wi-Fi and Bluetooth, and waterproof housing (up to 131 feet).