The price really varies from place to place. Only you can decide what it is worth to you and then stick to that amount and don't get caught up in a bidding war. They go from nothing up to $500.00. There are people out there that bid it up just to get the price up so be careful. Is is a private party selling just to you? If that is the case and you have an opportunity to buy it then I would probably offer between $100 - $150.00. I paid the most for my first one because I was unable to find one locally and bid on E-Bay and ShopGoodwill.com. The funny part was, I ended up with 3! Because after I got my first one, I didn't know how to cancel my bids on the other 2. It was okay though, I got one fore me and each of my daughters. (They don't really sew but figured you never know when you need to make a quick repair and these little machines are small so take very little room and they last forever.)
My eldest daughter refused to learn to turn it on, so now my sister has it and loves it. She takes it instead of her full sized Brother machine.