Purchase

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Purchase refers to buying an item from a vendor (or from a player via the Auction House) as opposed to looting it or receiving it as a quest reward. A purchaseable item is almost always BOE (or just not soulbound) and are generally easier to obtain than loot or quest rewards. A recepie for a profession, for example, is generally easier to find if it can be bought. The downside is that purchaseable items are generally less powerful (an extreme case being end-game armor/weapons) than BOP items due to their wide avaiability.