Mary M, I have a Pfaff 230 with all the accessories and just love this tank of a machine. I have a dating chart but it does not work like the Singer charts in that Singer goes from #xxxxx to #xxxxx for a year and the number of machines made plus the model number. There is a great vintage Pfaff group on Yahoo you might want to consider joining them for information. For Pfaffies such as myself, price would depend on condition and how much one wanted the particular machine. I have seen people pay a considerable amount of money for one in great condition simply because they wanted it regardless of the price.