Seven tips that could save you from expensive mistakes

Shop around. Never buy travel online without checking at least two or three sites for a lower price. Despite the many promises to the contrary, no single resource searches all airlines and hotels or always has the cheapest rates.

Read results carefully. Some travel Web sites bias their displays to list partner companies first. These rarely offer the lowest price, so scroll through all the results or sort by price when possible.

Beware of inaccurate displays and charges. We found that "fare jumping"—in which a price suddenly increases during the booking process—is a common problem even on the largest sites. Most will alert you to a sudden increase in cost, but not all do.

Decide quickly. Availability of airline seats and hotel rooms is constantly in flux, so do your research quickly to avoid losing a terrific deal to someone else.

Haste makes waste. Because some purchases are nonrefundable, a slip of a finger on the keyboard can cost thousands. The three-letter airport code for Orlando is MCO; one key away is MCP, and you've just bought a round-trip to Macapa, Brazil. Be sure to input correct dates, times, locations, and airport codes.

Check the fine print. Never do business with a site that doesn't clearly state its policies and a physical address. Even the best-known travel sites may have inadequate privacy and security policies.

Always use a credit card for travel transactions. As the Federal Trade Commission states (ftc.gov/bcp/conline/pubs/credit/fcb.shtm), under the Fair Credit Billing Act, using such a card limits your responsibility for unauthorized charges to $50.