Six costly mistakes you can make on travel booking sites

You might think that the power to compare travel prices online has created a buyer's market, since hotels and airlines must always jockey for your business with the best price. But that's an illusion.

Economics dictate that companies will do whatever they can to secure a profit, and so checking the Web for cheap airfare and vacation prices can be a process fraught with hidden pitfalls that aren't evident to you. Behind the scenes and under the hood, travel vendors have sneaky ways of making sure they still get the money they need to please shareholders despite the fact customers are always hunting for the lowest price.

I talked with Lauren Volcheff, a marketing exec for the company behind the Internet hotel discounter LastMinuteTravel.com, and she agreed to fill WalletPop readers in on a few tricks of the trade. Before you click "buy," know about these common mistakes people make when booking travel online: