I recently bought a retina 5K iMac and I would like to sell my iMac 2011. My iMac 2011 has the fastest processor at that time, 16GB RAM and 2TB hard disk, the video card was also the fastest at that time. I bought it for about $3000 back then. How much is it worth today? I don't want to rip people. I want to sell it at a reasonable price that people will buy it.