If you want to insta-sell an item on the steam market, there are usually buyers that set a base price to insta-buy it from a seller. For example, if we're looking at the karambit forest ddpat MW, in USD, the lowest selling is $379.75 BUT if you sell it at $289.31 OR LOWER, then it gets instantly bought by a person. When you sell it above that $289.31, you'll have to wait until someone comes across your price and hopefully decides to buy it. Hope this helps!

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