This is exactly right. They do not go for even $125 around here, central NY. This series (206) was Singer's first foray into ZZ machines, and they soon realized their mistake with the special needles. (At least that's my take on why they were not made for too many years.) Some folks really do love them in spite of needling special needles, which cannot be bought in local Walmart/Joann/quilt shops. They are not available in nearly as many types as Organ or Schmetz either.
I'm sure a few have sold on ebay for hundreds from sellers who tell lies about it's capability. I had one once in mint condition except for the damaged bobbin case. I gave it away.
"I think that's a 319 in which case it uses non-standard needles, 206 x 13. It's low shank and uses discs for more deco stitches. Make sure the bobbin case isn't damaged from people using the wrong size of needle. HTH."