Beware the high cost of a travel deal mistake.

“It is not just about the dollars saved,” says Michal Strahilevitz, an associate professor of marketing at St. Mary’s College of California. “It’s the thrill of the deal.”

A bargain’s siren song can lure even the most clearheaded traveler, warns Strahilevitz, who studies consumer psychology. Throw in a few points and miles, and people just lose it.

“They love to feel like they’re winning, even when they’re not,” she says.

Most travel deal mistakes happen during the planning stage. People spend hours trying to save a few dollars. They gloss over the terms and the fine print. A low price is all-important. And they’re drawn in by offers of freebies.

I’ve seen travelers — even experienced ones — make all of the following errors:

Caring only about price. When I talk to airline people about the recent cutbacks they’ve made in economy class, they have a ready answer. Travelers, they say, only care about one thing: a cheap fare. How far will they go to save money? Jessica Younginer, a Virtuoso-affiliated travel agent from Summerfield, N.C., has seen it all. “Clients want the cheapest airline seats instead of flights based on travel time,” she says. “Is it really worth two stops or long layovers to save $100? Time is money, and adding more steps to a flight itinerary leads to more chances for flight delays, maintenance issues and lost luggage.”

Ignoring the “gotchas. Bargain hunters are often so fixated on price that they don’t read the terms and conditions of their plane ticket or hotel room. “They don’t read the fine print,” says Daniel Guttentag, director of the Office of Tourism Analysis at the College of Charleston in South Carolina. Consider the hotel resort fee, often revealed after you’ve chosen a low rate and clicked on the hotel website or online agency to make a reservation. These surcharges can add $20 to $30 a night to the cost of your hotel.

Spending many hours to save a few dollars. Speaking of time and money, here’s another big travel deal mistake: failing to factor in the value of your time. People will spend hours looking for the best deal. They may find a lower airfare and save $30. But is it worth it? If it is, maybe they shouldn’t be flying anywhere. They probably can’t afford it.

Glossing over the terms. It happens to people who book trips through an online travel site. They fail to review the cancellation terms, which can be restrictive. “These sites can occasionally offer some savings,” says Joanne Cunningham, director of sales and marketing at Dunes Manor in Ocean City “But many times, they don’t have guest-friendly cancellation or alteration policies.” A lot of hotels offer at least a 24- to 48-hour cancellation or modification period before your check-in. If you prepay through an online agency, you might not be able to make a change to your reservation or get a refund if you need to cancel. Cunningham says you should consider a direct booking with the hotel, online or by phone, and steer clear of the slightly lower “prepay” rates offered by an online agency.

Being blinded by a low price. Experts say bargains can short-circuit travelers’ skeptical side and lead to travel deal mistakes. Consider a hypothetical four-star hotel room offered at half the going rate. “Do your due diligence,” says Reneé Rayles, a frequent traveler and author of “The Super, Sexy, Single Mom on a Budget.” “Often, they’re renovating, or the pool is closed. Look in the fine print to see if there’s more information about the time you are staying there and any exceptions about amenities.” Bottom line: If something looks too good to be true, it probably is.

Allowing a bargain to control your itinerary. Some travelers find a great deal and change their plans to accommodate the bargain. For example, they may have a plan to vacation in Ocean City but change it when they find a cheap hotel rate in Hilton Head, S.C. Planning your vacation around a bargain is a surefire way to get a trip you don’t want.

Getting misled by miles. Frequent flier miles and hotel points can lure even savvy travelers to blow their budgets. The bargain may be seductive, but add miles to the equation and oh, boy! You’re probably not thinking straight. “If you’re racking up a bill on your travel credit card so that you can get a free flight, you should understand that points and miles aren’t free,” warns Greg Mahnken, an analyst with Credit Card Insider, a site that advocates the responsible use of credit cards. “Consumers are prone to spending more on a credit card than cash, even without the attractive feeling of earning miles and travel rewards.”

Avoiding these mistakes is easy, at least in theory. You can set a reasonable budget for your next trip, based on previous vacations and your research. Read all the terms carefully. And think of any miles or points as a byproduct of your purchase — not the reason for it.

But if there’s one thing I know after writing travel advice columns for decades, it’s this: You’ll still fall for it.

That’s because of the way you’ll respond when a deal flashes across your screen with a bonus points offer. Researchers like Strahilevitz spend their careers studying human psychology, and some of them help travel companies design ever more effective ways to lure customers. (For the record, Strahilevitz is not one of them.)

So until I find a foolproof way to get around the travel industry’s enticements, I have just one more piece of advice: Be careful out there.

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