While under the opaque pricing model, users bid for services at discounted prices and Priceline earns the difference between the price an individual is willing to pay and the price charged by the travel service provider.

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Brokers push them, he says, because the pricing is opaque and most customers will never see a bid-ask spread.

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Instead, its interest is in providing its users easy access to airline flight and pricing data and giving online travel agencies the ability to bid on the sale of tickets to Google users looking to buy.

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Now you could be faced with two demands: potential sellers could realize that they are under pricing their wares and dramatically raise the price, or potential buyers could quickly bid up a toy to something that approaches its fair market value or beyond, creating a bubble.

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