If possible, buy from someone you know. you can look at it--on ebay you really take a chance. if you buy on ebay,be very specific to the seller that you need it packed right. Google "how to pack a sewing machine for shipment". many a good machine has been ruined by poor packing.
you have to decide if you want a "beauty" or something to sew with. you will pay less for one that the decals & paint are chipped, etc. but the guts of these little babies are all the same. It needs to work well when you buy it.
sometimes you can tell by a sellers words if you should shy away from bidding. "I don't sew, so don't know too much about this "; the light works ; good for it's age; bought as is at an estate; are all clues that they do not know what they are doing. a knowledgeable seller will tell you condition in terms of scratches, decal wear, when it was serviced, will clean machine before photo shots, will guarantee the condition as stated, etc.
We clean, oil, etc. a lot of machines that are bought on ebay. so, add the cost of a good cleaning,oiling,etc to the price you are paying for the machine.
I think the machines made before 1953 have a better coat of paint. the scroll faceplate can be put on any machine,but were standard until (I think)1949-50.
We sell 221's for $375-400 for really nice ones. those that are cosmetically challenged $275. completely cleaned, etc. guaranteed. there are fantastic deals out there, if you want to wait until you stumble on one. they are great machines for classes, etc. so soothing to sew on.
We went to practically every garage sale around here (and we must be garage sale capitol of the world !) this season & only found 1 Featherweight--and that only because we happened to talk long enough to someone that she "remem
bered" a machine in a "little black box".
Here's to Happy Hunting & Happy Sewing on the vintage Singer machines. owner of WAY too many !