If you’re selling a car, piece of jewelry or other expensive item to a stranger, you might insist on being paid with a bank-issued certified check. After all, these are safer than personal checks, which could bounce like a rubber ball. (Certified checks are backed by the bank, so they can’t bounce due to insufficient funds. And banks generally are required to honor a certified check that’s presented for payment, making it difficult or impossible for someone to stop payment.)

But imagine if weeks after you deposit the check, your bank notifies you it was counterfeit and demands you return the money that was credited to your account.

Yes, it happens.

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With a lot of know-how and modern computer and printer technology, scammers can produce very convincing counterfeits, complete with the correct addresses and routing numbers for the institutions on which they supposedly were drawn. The fakes even may have watermarks and display a notice about the security features the check or money order has to prevent fraud.

Banks and banking regulators routinely issue warnings about the latest institutions that have had their checks or money orders counterfeited. The problem has become so widespread that federal and state consumer and banking agencies, including the Federal Trade Commission and the Comptroller of the Currency, have issued general warnings. Some banks and credit unions have done the same, including the Virginia-based Federal Reserve Bank of Richmond. And the National Consumers League has devoted a website to the problem, FakeChecks.org.

When you deposit a fake cashier’s check or money order, your bank will credit the account within one or two business days. But it can take weeks for the fake check to make its way to the financial institution that supposedly issued it . And that’s when the counterfeit will be discovered. Once your bank finds out, it will demand a return of the money or even remove it from your account automatically if you haven’t withdrawn it.

Popular cashier’s check scams: Sellers and job hunters beware

Some scammers target people who sell merchandise or look for jobs online.

In the merchandise scam, they may send a counterfeit check or money order to pay for an item. By the time you find out the payment is bogus, the scammer has disappeared with whatever you were selling. In many cases the scammer sends a check or money order for more than the agreed-upon price. He may say it was a mistake or explain the additional amount was meant to cover unexpected shipping charges or something else. You’re then asked to wire back the difference, in addition to sending the merchandise, setting you up for a double loss.

And in another version the scammer, after sending the bogus payment, cancels the sale and asks you to wire back a refund.

In the employment version of the scam, you receive what appears to be a job offer, with a check or money order included to cover the expenses associated with some service the “employer” is asking you to perform. It’s often a mystery shopping assignment — you may be asked to evaluate a money transfer service by wiring a certain amount to someone in another country. You’re instructed to deposit the (fake) check or money order and then withdraw part of the money to pay for the transfer. The money that’s wired as part of the “evaluation” ends up being lost, along with amount you were told to retain as payment for your services.

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How to protect yourself

Because check related scams change all the time, it’s important to use your judgment and question anything that seems suspicious or too good to be true. For instance, ask yourself why anyone would send you a check or other form of payment unexpectedly or for an amount that’s more than you expected. Scammers can be very creative and convincing in their explanations, so remain vigilant.

Here are some more specific precautions to take.

Use a third-party payment service. When offering something for sale, consider using a third-party payment service, such as PayPal, which protects you against counterfeit payments and other types of fraud. Be sure your transaction qualifies and read the terms and conditions.

For direct sales, you can use an independent escrow service, such as Escrow.com. But fees can be significant. To handle the sale of a $15,000 vehicle or other item, Escrow.com charges nearly $190, with a $25 surcharge for buyers outside the United States. The fee for a $1,000 sale is about $35.

Don’t simply agree to use an escrow service the buyer recommends. Some escrow services are phony. Check any service out yourself. And don’t click on a link or web address the buyer provides. It could be a phishing scam that takes you to a counterfeit website. Search for the name in your browser instead.

Authenticate the check or money order. If you still want payment by cashier’s check or money order, verify its authenticity by calling the issuing financial institution. Don’t call any number that appears on the check or money order itself. (It too could be bogus.) Instead, find the institution’s telephone number yourself.

Meet the buyer at the bank. An alternative, if it’s a local transaction, is to meet the buyer at a nearby financial institution and observe him purchase the check or money order.

Verify cash, too. Cash also can be counterfeited. If you get bogus greenbacks, you may be out of luck. Many homeowner’s and renter’s insurance policies automatically include coverage for up to $500 or $1,000 in losses from counterfeit cash and with no deductible. But that may be only a fraction of your loss in a major transaction.

Related: 5 Signs That Bill May Be Counterfeit

Beware of overpayments and wire requests. Be suspicious if anyone who sends you money unexpectedly or pays you more than the amount you expect, with a request that you return use a wire service to return the difference. Be suspicious any time a person asks you to wire money, especially to a third party or to another country.

Complain. If you end up being ripped off despite your diligence, complain to your state consumer officials, the Federal Trade Commission and, if the transaction involved online fraud, the Federal Bureau of Investigation’s Internet Fraud Complaint Center. Scams involving the mail should be reported to the United States Postal Inspector Service.

Anthony Giorgianni is a veteran consumer and finance journalist who worked for Consumer Reports and Connecticut’s Hartford Courant newspaper. He specializes in consumer law; fraud and scams; shopping and saving money; consumer credit; saving and banking; car buying, leasing and maintenance; money management; identity theft and personal privacy; charitable giving and more.