Walmart offers the refurbished Vizio 50" 4K 2160p WiFi LED-Backlit LCD Ultra HD Smart Television, model no. M50-C1, for $399.99 with free shipping. That's $250 under the best we could find for a new one today, although we saw it for $31 less a month ago. It features a 3840x2160 (2160p) native resolution, Smart TV (with access to Netflix, Hulu Plus, Pandora, and other Vizio Internet apps), USB, and five HDMI inputs.
Of note, no warranty information is provided.