Grace,
According to ISMACS {
http://ismacs.net/singer_sewing_mach...l-numbers.html } that serial number indicates it's a 99K, 1 of 50,000, allotted 1-28-57.
There's nothing wrong with a 99K, but no way is it a 201 series machine.
As Rodney said, can you post the listing? Either the seller has the wrong number or misread it.
Joe