Costco offers its members the Vizio 80" 4K 2160p LED-Backlit LCD Ultra HD Smart Television, model no. M80-C3, for $3,699.99 with free shipping. (Non-members pay $185 more, so it's best to sign up for a $55 1-year membership.) That's the lowest total price we could find by $100. It features a native resolution of 3840x2160p (2160p), LED backlight, 802.11ac WiFi, Smart TV apps (YouTube, Netflix, Hulu, etc.), USB port, five HDMI ports, and two-sided remote. Deal ends August 24.