What makes this person think this machine is so rare? From the picture the cabinet looks very nice, so it may not have been used much or it has been refinished. Wonder what they would consider a low-ball offer? If it doesn't sew then it's just a table. I don't know which model it is, but I can't see that is would be worth much unless you test it out and find that is does everything you want it to do. I have a (1949) Singer 15-91 in a cabinet and since it was the one I learned to sew on to me it is priceless, and my cabinet looks like it has been well used. So if I were to respond to the seller I would ask them why they believe it to be rare, just to start with.