Some other things you may want to include:
If takes a flat shank needle which side is the flat side one?
Does it take a unique needle? e.g. 20x1, CC1221, 206x13
Is it a flat shank or round shank needle?
Is it a low shank, high shank, extra high shank, slant shank or top mount or other?
The belt size - for electric machines. (This may may also include some cleated belts - one would also need number of cleats)
What does this machine need to get in working condition?
What accessories could be added that are wanted? e.g. cams, straight needle plate, additional feet.
Janey - Neat people never make the exciting discoveries I do.