You can price the machines as you wish but think of this...ebay machines sit and relist and sit some more,why? Because the prices are nuts! Pinside prices in archives show what we are willing to pay. So with that being said you do not want to be an ass and raise a price of machine during or at a show because someone else is selling his for $300 more than you. So start a little high and during show come down little by little until you get a bite but not go below your personal reserve. The market will decide the buying price if you're willing to sell your machine at that price. In the end you may take the machine back home with you and enjoy it until next show.
-Mike