I have bought MANY things off of ebay - no sewing machine though. However, using paypal you are protected if it isn't like its described in the picture.
I have, however, been burned when I bought a machine off of Goodwill. I received the machine and it HAD BEEN DROPPED prior to shipping. The whole thing jammed up in the machine. The picture showed in all intacked. GRRR And they don't have a return policy. And it would've cost me a lot to ship it back etc. I decided it was a learning lesson and I stick to ebay. 8/