The current auction house was implemented 15th January 2013. Before it there was a slightly different system in place.
Only items marked by the game as rare (1000 or less in circulation) can be added to the auction house, however they will stay on auction if they go over this limit once already added. You choose a number of days between 3-30 for your item to go on the market.
All auctions start at $1 and there is no reserve or starting price system. The game will automatically bid for you up until the maximum price you have set when you bid. This is to prevent bid sniping right at the end of the auction time. There is a live timer counting down to the end of each bid on the page, which can end at any time of the day. If you are outbid or your item sells, your money is returned in the form of a cashiers check. These can be redeemed at the city bank, or are returned automatically after 24 hours.
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