An unscrupulous sales technique where customers are initially quoted a lower price, then informed that there has been a mistake and the actual price is higher. Customers who initially agree to pay the lower price are much more likely to continue with the sale at the higher price.
Example: A car salesperson tells her customer that car X is a steal at only $12,000, and he agrees to buy it. After ducking into the office to get the paperwork and consult with her manager, however, the sales associate comes back to inform the potential buyer that there has been a mistake, and the price is actually $12,850. He is displeased but agrees to pay.