Here is another in our series about Web sites that serve as useful planning tools for budget travelers. HomeExchange.com allows you to swap homes with other travelers who want to avoid high hotel prices. The data base connects people by geographic area, and after a membership fee is paid, each exchange is made without a fee. This article shows you how it works. If you're comfortable with the idea of swapping homes, you could save quite a bit of money on your next trip to a pricey location.