<p>In this Nov. 28 photo, a Target shopper uses her iPhone to compare prices at Wal-Mart while shopping after midnight in South Portland, Maine. Increasingly, buying products online is like trading stocks: you can buy a copper mug or a coat and then hours _ or even minutes later _ it can go up and down in price.</p>
December 19, 2014
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December 19, 2014 8 p.m.
At what cost?
Constantly changing online prices stump shoppers
NEW YORK - Online shopping has become as volatile as stock market trading. Wild, minute-by-minute price swings on everything from clothes to TVs have made it difficult for holiday shoppers to "buy low."