Firstly such a reference request here may be off topic. Also i am not sure if it possible to do arbitrage in e-bay system unless you know what is the current price for an item to be bought in different sub-ebay systems(ebay of different countries). I am unsure as a seller what information is available to you. Arbitrage could only be done when there is known price u can buy at and a known price u can sell the goods at in different ebay markets, also this would not necessarily be completely risk free, as you might be open to exchange rate movements. Also to classify as arbitrage it has to be an instantaneous transaction without holding the merchandise or goods on your own book. Secondly in case of e-bay transaction you may end up needing to ship, which may introduce additional costs, some what analogous to transaction costs probably, but may be much higher in proportion (u may be able to control this by trading in only goods with low shipping costs, so no cars and couches perhaps). This may reduce the chance further of arbitrage unless the person you bought from was selling it at a much lower price than the current market price and the person who is buying is willing to buy probably at a much higher price.