I wanted a featherweight to take to classes at my quilt guild, so after searching a while, I found one on ebay, for around $178, shipping included. After cleaning and oiling, she runs just fine, although the japanning on her bed is chipped. There is no rust, however. Then, we found another on Craigslist for a very reasonable price, can't remember exactly, but less than we paid for the first one. It also runs nicely. The third one was a birthday present from DH last December. She runs fine, but has a musty odor. I suspect it may be the oil pad, or the case itself, hard to tell which. And the case is in bad shape. I am tempted to just remove the torn covering on the case and refinish the wood.
I expect that someday my featherweights will end up in the hands of my grandchildren. I just hope they recognize their value.