It should be priced at the maximum value someone is willing to pay for it… and naturally in market economy it often will. The Artist needs to also make a living and not all of their artwork will sell at earth shattering prices. It seems just as arbitrary to limit the price of the item to a fraction of the value of a single item. I do wish more art was auctioned rather than come with a fixed price tag to make the market more fluid and less egotistical.