Please let me know if you are able to find a dealer stupid enough to go along with this.
Built into the dealer's costs are rent and other overhead, including the 2% or so merchant charges for Credit cards. I wouldn't think that a dealer would sell an item for $100 and then repurchase such an item for the same amount of money barring any upward fluctuation in value. If he or she did, they wouldn't last too long in business, and would most likely be featured in the annual "Darwin Awards."
If you find them, please let me know so I can prey on them before the other wolves have picked all the meat off...