Shoot, I am of the 'make an offer' school. I would point out all that is wrong with it, and offer what you'd like to pay. Worst they'll say is no. I got my dirty guy for ten. I wanted it so much I would have gone fifteen!
And Joe, my goodwill had three machines today. a (med old) Singer - the one with brown on the face, and little pics of the stitches . . . kind of square. An old japanese zig zagger, I don't remember the badge. It looked terrible. the finish was discolored, it was filthy. It had a box of attachments in that little slot on the left, but that was it. The light came on, and tried hard to stay on. the motor came on, whirred, no movement. turning the wheel moved nothing either. It smelled bad as it tried to work, and the case was banged, dented, and ground-in dirty. $14.99. Not EVER.
Didn't price the newer one.
Then, there was a smallish white in a cabinet - looked to be in nice shape. $9.99. Of course, it was sold. The drawers were empty - If Margaret was smart, she took that with her! (her receipt was taped on it, with her name!!)
the difference in those prices is just crazy!!