You might look though the vintage thread to see prices people have paid for some of their machines. I know for example some of the more common machines generally can be had for $50 or less - with and without a treadle cabinet. I got mine (a 66 treadle with cabinet) for $40 and it needed a lot of elbow grease. I also purchased an excellent condition (and recently used and loved) 115 for $75 without cabinet.