Best Buy offers the Acer 28" 4K FreeSync LED-Backlit LCD Ultra HD Monitor costs $249.99 with free shipping. That's the lowest price we could find by $105 and a great deal for a 27" or 28" 4K monitor in general.

It features a 3840x2160 (4K, 2160p) native resolution, LED backlight, 1ms response time, and DisplayPort and HDMI inputs.