Usually around $75-125, but the first one to be put on eBay went for $700.
It also helps if you have over 200+ Feedback when selling something with over 98% atleast positive.
That can also influence the prize. If Person A sold a card supposely worth 200 on ebay with 5 feedback rating he wont get near as much as Person B who has 200+ feedback.
JMO,
Drew