Walmart offers the refurbished Sharp 55" 4K LED-Backlit Ultra HD LCD Smart Television, model no. LC-55N6000U, for $369.99 with free shipping. That's $47 under our mention of a refurb from two days ago and the lowest price we've seen for it in any condition. (It's $60 under the best deal today for a refurb.) Features include a native resolution of 3840x2160 (4K), WiFi, web browser and streaming apps (including Netflix, YouTube, and Vudu) and four HDMI inputs.
A 90-day warranty applies, although it's unclear who backs it.