Welding Tips and Tricks

Hey guys I have an old mug welder I just paid to have it cleaned up and tested as well as bought a new gun. It welds great but I'm looking to sell it because it is big and my shop is small. What should I sell it for I have no idea. It has a 60% duty cycle at 200 amps which so I've been told makes it around a 250amp machine. Any help would be greatly appreciated.

I have seen them from $300 to $1500 depending on condition. I have one that appears to be in better shape than the one in the picture and mine has the stitch and spot features also. I wouldn't sell it for 2k.