As easy as it is to become obsessed with the World of Warcraft Auction House, waiting for item prices to drop and putting up rare treasures for bidding with the hopes of pulling in a nice virtual profit, that's child's play compared to what Blizzard's doing with Diablo III. The online Auction House to be implemented through Battle.net for Blizzard's upcoming action-role-playing game will allow you to put in-game items up for sale for real money. You set the price, other players bid or buy out, you make the profit.
That means when you're in a dungeon, slay a boss and get a super rare item, it's exciting not only because it'll help you kill stuff more effectively, but also because you could potentially profit from it in real life. The Battle.net Auction Houses will be separated based on region. While there won't be one single Auction House for the global player base, all players within a region will have access to the same one. Eventually Blizzard may allow players to check auction houses in other regions using different currencies, but at launch that won't be the case.
Auction Houses will be split into in-game currency versions and real money versions. If you don't want to deal with using real funds to buy items (or virtual), you don't have to. Most of everything you find in Diablo III, from skill-enhancing runestones to rare items to in-game gold can be put up for auction. The system is Blizzard's way of taking ownership over the black markets that tend to pop up around item-based games.
It's also Blizzard's way of making more money. There'll be a "nominal" flat fee charged by Blizzard for every item you post on the Auction House, as well as a transaction fee when the item is sold. It's important to note that this is a fixed fee, so it does not scale depending on the rarity of what you're selling or the associated price. For those who might cry foul at this, Diablo III executive producer Rob Pardo points out, "We could have chosen to do a model of 'we're just going to sell rare items on our website for X amount of money'. We just didn't feel like that was the right decision for us." The reason Blizzard says the listing fee exists is to guard against players spamming the Auction House with junk. It's likely at launch you will get a handful of free listings per week to try it out.
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