Learn how to avoid the most common swindles—from high-tech password theft to low-tech door-to-door hustles.

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Social-Networking Rackets

The rip-off: Websites like Facebook have become fertile ground for scam artists who hijack members’ accounts to spread viruses and spam. Via news feeds and messages, they distribute videos or phony gift certificates that appear to be from friends but, when downloaded, install damaging software on your computer. Two cons going around Facebook this year: a page offering a $1,000 Ikea gift card in exchange for your personal information; and messages asking for money, supposedly from friends in trouble who are traveling overseas. These scams can spread through e-mail, too. A recent one, a bogus coupon for a free bag of Doritos, did not harbor a virus, but it did cause Frito-Lay a big headache.

The tip-off: Although lots of legitimate companies send customers special offers by e-mail and use Facebook to market promotions, these deals rarely involve opening an attachment. As for those $1,000 or $500 gift cards? Facebook warns members on its security page (facebook.com/security) to be wary when overly generous offers are dangled in front of you. And any request for money should set off alarms. Last year Erin Fry, 41, of Chelsea, Michigan, received a Facebook message supposedly from her mother saying that she had been robbed while on vacation, along with a plea for money. “I knew my mother wasn’t in Europe,” says Fry, “but some of her friends who also received the message thought the request was legitimate, since my parents do travel frequently. Luckily no one sent any money.”

How to protect yourself: Don’t be seduced into opening an attachment unless you’re absolutely certain of its origin. If the offer or video is tempting and it seems legit, first peruse websites like Snopes.com (a fact-checking source for Internet rumors) and Consumerist.com (a consumer-advocacy website); they’re quick to publish news about fake deals and viruses making the rounds (no, the Olive Garden did not recently offer Facebook “fans” $500 gift cards). You can also go to the Coupon Information Corporation (cents-off.com), which lists counterfeit coupons. To avoid catching a virus—or getting scammed—on Facebook, don’t click on links in messages from friends that seem out of character, especially ones soliciting money. Would a friend really use social media to ask to borrow cash? Probably not.

Phishing for Passwords

The rip-off: Some fraudsters try to trick you into revealing personal information, like passwords, credit-card numbers, and account details, by pretending to be your bank or credit union or a government agency. This crime is so commonplace that it has its own name, phishing. How do these crooks do it? Often you’ll receive an e-mail or a text message that appears to be from your financial institution that says your password needs to be reset or you need to update your account information. Instead, you might be directed to a website to fill out a form that is set up for the purpose of stealing your personal data. Or you might receive a recorded phone call asking you to call back a number and enter your account details via an automated system. (This version of the scam is called smishing.) Think you would never be taken in? Consumer Reports estimates that 1 million households gave phishers confidential material within the last two years, leading to estimated losses of $650 million.

The tip-off: It’s not easy to sniff out these scammers, since they are so tech-savvy. “Some phony phishing websites use logos and text copied from genuine bank sites,” says Sid Kirchheimer, author of Scam-Proof Your Life (Sterling, $16, amazon.com). Swindlers can even program their phones so that an actual bank’s name shows up on your caller I.D.

How to protect yourself: If you get a call that’s supposedly from your lender—which might happen, especially if you’re traveling and they are concerned about any unusual purchases—hang up and call the number listed on your bank statement or credit or debit card. If you have doubts about a text or an e-mail that you receive, delete it. Then phone your bank to resolve any questions and to notify it about a possible scam.

Shady Online Sellers

The rip-off: Say you buy something online and it never arrives, or the item isn’t what you thought you were buying. You’re not (remotely) alone. This type of fraud continues to be one of the top complaints tracked by the Internet Crime Complaint Center, a partnership between the Federal Bureau of Investigation and the National White Collar Crime Center, a nonprofit that helps law-enforcement agencies com-bat financial and high-tech crimes. It happened to Stephanie Welbourn, 27. She used Craigslist to buy tickets to see the musical Wicked on Broadway last December. When she and her mother got to the theater, they found out the tickets were fake—after paying $240 for the pair. “I felt sick to my stomach,” says Welbourn. “I thought I had checked everything out.”

The tip-off: According to Welbourn, the tickets looked completely legitimate: They had a bar code, the terms and conditions were printed on the back, and they were even perforated where the stub would be torn off. The only giveaway was that one digit in the theater’s street address was wrong. Buying tickets from a reseller is always risky. And Craigslist is a hotbed for scammers, who thrive on the site’s anonymity. If a seller gives you just a cell-phone number (not a land line), which is the only contact info Welbourn had, that should be a red flag. Why? Cell phones can’t always be tracked. Other signs of a dubious deal: a seller who asks you to wire money, a retail website that doesn’t list an address or a phone number, and a company name that doesn’t have much of a presence or any reviews online.

How to protect yourself: Verify that the item you’re purchasing on Craigslist (or any reseller website) is genuine and will function as advertised. If there’s no way to do this, just don’t buy it. (For example, if you’re purchasing tickets and the seller won’t meet you at the theater or arena and wait to be paid once the tickets scan, don’t hand over the cash.) And confirm the seller’s name and address before you meet—always in a public place—so you have contact information in case things go awry and you need to report the fraud. With online retailers, always research the site’s return policy before hitting the checkout button, and pay with a credit card so you can dispute the charge if there is a problem later on.

Charity Cons

The rip-off: Every time there’s a disaster, like the earthquake in Haiti or the oil spill in the Gulf, bogus charities arise. They pretend to seek donations for the relief effort, then pocket the money themselves.

The tip-off: Be suspicious of any organizations you’ve never heard of that request money through e-mail or social-networking sites. And scrutinize charity names carefully. Like phishers, these scammers are sophisticated about impersonating well-known entities, sometimes using a name or a Web address that sounds like a recognizable nonprofit, such as America’s Red Cross instead of the American Red Cross.

How to protect yourself: Stick with charities that have received tax-exempt status from the Internal Revenue Service. Ask them to e-mail you a copy of their charitable-status letter. Or go to irs.gov/charities to verify a group’s nonprofit status. You can also search the Better Business Bureau’s Wise Giving Alliance (bbb.org), which evaluates charities based on criteria such as percentage of donations going to overhead costs and percentage going to victims. To report suspicious solicitations, contact the National Center for Disaster Fraud (disaster@leo.gov), established by the U.S. Department of Justice after Hurricane Katrina to investigate criminals who target donors.

Vacation-Rental Ruses

The rip-off: Fraudsters post a home to rent, but it doesn’t really exist. Or it does exist but isn’t owned by the person who placed the ad. In some cases, con artists cut and paste photos and descriptions from legitimate rental listings, or they make up bogus ads using photos of real apartments or homes. Brigid Schulte, 48, of Alexandria, Virginia, almost fell for this. She seriously considered renting an apartment for a last-minute trip to New York City that she found listed on Craigslist. The ad featured gorgeous photos and the lure of a low price—$150 a night for a two-bedroom penthouse.

The tip-off: Online misrepresentation is one of the most common frauds highlighted at the consumer-education website LooksTooGoodToBeTrue.com, which was developed by a joint federal law-enforcement and industry task force to help consumers avoid becoming victims of Internet fraud. Steer clear of owners who ask for payment to be sent immediately via wire. Schulte was saved from this crime, and from losing about $1,000, by a Western Union employee who advised her not to wire money to a stranger. After some digging, Schulte realized the scammer had posted similar fake ads under the same name and using the same photos. Other red flags include landlords who want you to send money to a third party (or overseas) and deals that seem, yes, too good to be true.

How to protect yourself: If you’re going to rent a vacation home sight unseen, stick with trusted websites, like HomeAway.com and VRBO.com, which charge home owners a listing fee (Craigslist ads are free). And always pay with a credit card or PayPal, which gives you more protection. Both HomeAway and VRBO will refund you the money if an ad is fake, and they also sell rental-guarantee policies. You pay an extra $39 on a $1,000 rental, say, and if the post misrepresents the property, your money is returned. However, even using one of these sites doesn’t give you 100 percent protection, since they do not take responsibility for listings on their sites. Renting through a real estate agency can be a safer option, especially if you’re vacationing far away and can’t visit the home before you commit. Agents generally screen the properties they represent and can provide specific information and accurate photos for each one.

Door-to-Door Hustlers

The rip-off: These folks may ring your doorbell offering to clean your chimney, fix your roof, replace your siding, remove dead trees, or do odd jobs. This is a year-round problem—particularly for residents of older homes, which are often in need of repair, according to Sally Hurme, a senior project manager for AARP, which tracks schemes that prey on its members. Another version of this scheme involves teenagers or even adults selling candy or magazine subscriptions for school fundraisers. (This scenario can be legitimate, too, so don’t automatically write off these sellers.)

The tip-off: “A con artist’s spiel is usually something like ‘I was just in the neighborhood, and I have some supplies left over from the job I did for your neighbor down the street,’ ” says Hurme. These fake contractors look at mailboxes to get the name of a real neighbor and often dangle a discounted price. They typically ask for a hefty cash deposit, often hundreds of dollars. Then they disappear to get supplies or start the job and never return. “The come-ons they use are proven pitches similar to those of actual professionals: They’re experts; they can offer a reasonable price; they can save you the trouble of finding someone else to do the job,” says Hurme. An out-of-state license plate on the person’s vehicle, a hard sell (the offer is good only today), and demanding payment up front are all signs of a con. Fundraising claims can also be suspect, especially if there’s not a charity name you can search for online. But at least the fallout with fund-raising scams is low: If that money isn’t really going toward a marching-band trip, you’re probably out only 20 bucks.

How to protect yourself: Never hire a handyman on the spot. If someone comes to your door, take a name and ask for references. Check the contractor’s name or company with the Better Business Bureau or your state consumer-protection agency (go to consumeraction.gov/state.shtml) and conduct an online search to see if it turns up any complaints or lawsuits. And call your city’s or state’s contractor-licensing bureau (search by state at the website of the National Contractor License Service, clsi.com) to make sure the person or company is licensed to do things like electrical and plumbing work. “Even if somebody shows you a license, it could be outdated or falsified,” says Hurme. As for those school fund-raiser pitches, there are scams that exploit kids to sell subscriptions that never arrive; the Better Business Bureau receives more than 1,000 complaints about this each year. Your best defense? Don’t pay for anything unless it’s in your hands at the door. If you can’t resist a face-to-face appeal, the Federal Trade Commission’s “cooling off” rule gives you three days to cancel purchases over $25 made at your home. If the seller won’t give you a cancellation form when you ask for one, which is required by law, just say no to the offer.

Debt- and Credit-Repair Scams

The rip-off: If you have bad loans or a bankruptcy on your credit report, you may be advised by dubious credit-repair companies to stop paying your creditors and deposit money into a special account instead. In theory, you’ll pay off your debt in one lump sum, thereby saving you money; in the meantime, the debt-settlement company promises to negotiate with your creditors to get them to accept less than the amount owed. In reality, they withdraw fees (up to 20 percent) from your account for their “services.”

The tip-off: These shady businesses typically deduct their fees long before they help you become debt-free, says Gail Hillebrand, a senior attorney with the Consumers Union, the nonprofit organization that publishes Consumer Reports. (However, starting this month, they cannot charge you until they settle some of your debt; if they do, they’re violating the law.) Another sign of a dishonest outfit: It advertises on the radio and late-night TV, touting a stellar track record. A government report found that less than 10 percent of clients successfully complete these debt- and credit-repair programs.

How to protect yourself: Stick with a legitimate nonprofit counseling outlet that has an established record of helping people, the National Foundation for Credit Counseling (nfcc.org). Hillebrand also advises people to try to negotiate directly with their creditors. You might be able to get just as good results doing it yourself.

Counterfeit-Check Fraud

The rip-off: This crime comes in many forms, but each takes advantage of a shocking loophole in the banking system—namely, that when you deposit a check, the funds are quickly made available in your account before the check officially clears. For example, swindlers make a deposit on an apartment lease with a counterfeit check, then ask the owner to return the funds immediately; the owner is now out that money twice over.

The tip-off: “If somebody sends you a check and then asks you to wire money back to them, it’s absolutely a scam,” says John Breyault, vice president of public policy for the National Consumers League, a nonprofit consumer-protection organization, which identified fake checks as the top scam in 2009 based upon complaints the group received. Shawn Mosch, 39, of Bloomington, Minnesota, started the advocacy group Scam Victims United with her husband, Jeff, after they fell for this scheme. They were selling an old Buick, and the buyer told them a friend owed him money and would send them a cashier’s check directly. When it arrived, it was made out for $7,000 more than the agreed-upon price, so the Mosches wired the difference to the buyer after they assumed the check had cleared. “I thought I had asked the bank the right questions: Is the check good? Has it cleared? Is it verified? And they told me yes to every question,” Shawn said.

How to protect yourself: “This scam preys on people’s unfamiliarity with the check-clearing process,” says Breyault. (That includes your own bank’s employees.) When you deposit a check into your account, even though the funds show up, that doesn’t mean that it is valid. Until it clears the issuing bank, a process that can take up to a couple of weeks, you don’t really have the money. So never spend the funds you have deposited or return the money until the check is fully processed. To find out a check’s status, call your bank twice (talk to two different workers in case one doesn’t understand the process) to verify that the check has been fully processed. Otherwise you lose the money if the check is a fake.