Not long ago, a couple of visitors to Northeast CONTACT brought in copies of “checks” they had received in the mail, along with invitations to become “mystery shoppers.”

Our radar went on high alert. “Mystery shopping” is one of those terms that many people automatically equate with “scam.” While the potential for abuse is there, the truth is that millions of mystery shoppers are working every day in all kinds of businesses across America.

And when unsuspecting people are too trusting, fraud artists are using some old tricks to separate them from their money.

Let’s look first at the legitimate work. Mystery shopping involves buying merchandise, making returns and doing everything any other customer would do. However, the “undercover shopper” also writes a report on things such as service, quality, cleanliness of the store, and so forth. Businesses hire mystery shoppers as a quality control measure and to spot weaknesses in their sales and service efforts.

Almost any business that interacts with customers might use mystery shoppers, even government agencies. There’s even a Mystery Shopping Providers Association, with member companies agreeing to an approval process and pledging to uphold ethical standards.

Mystery shopping sounds like an easy way to make money and possibly keep some good stuff in the process. In reality, it’s work that demands good organizational and writing skills and patience. Making a living at it probably means working for several mystery shopping companies and doing related work, such as market research. One source says an experienced mystery shopper might make $10 an hour or a bit more.

You are hired by these companies after filling out an application. One tip on avoiding being ripped off: There is no fee to submit an application. You might be put off by some of the questions you’re asked on the applications, including age, race, number of children and other personal information the companies use to prepare shopper profiles. They’re looking for specific kinds of customers, and if you fit their needs – and aren’t opposed to putting it on paper – you may be hired.

What legitimate mystery shopping firms do not do is send out letters with what appear to be cashier’s checks purportedly worth thousands of dollars. In fact, they’re worthless, and the letter telling you to call the writer’s office for instructions on cashing them and wiring a portion of the money to them is a road to financial ruin.

Fraud artists can make such checks look very real, and often your bank may not discover the check is counterfeit for several days. Our visitors mentioned above brought in instructions to shop at a couple of major chains and to “check out” the effectiveness of Money Gram transactions by wiring more than $1,200 to the letter writer’s office.

This is called the “overpayment scam,” and it’s been around for a long time. Don’t fall for it. Also:

. Don’t give your credit card or bank account numbers to a firm seeking a fee application; never pay to apply.

. Don’t respond to unsolicited invitations to become a mystery shopper. If you’re serious about entering the field, search online for legitimate concerns; many legitimate firms have applications you can download and mail in.

. Use caution when filling out applications online. Enter personal information only if you are comfortable doing so and only on a secure Web site. The address should begin https and you should see a small image of a lock at the bottom of your computer screen.

Above all, do your research and remember the adage: If it sounds too good to be true, it probably is.

Consumer Forum is a collaboration, now in its 30th year, of the Bangor Daily News and Northeast CONTACT, Maine’s membership-funded nonprofit consumer organization. Individual and business memberships are available at modest rates. Interested and motivated prospective volunteers are always needed and welcomed to apply to help with our mission. For assistance with consumer-related issues, including consumer fraud and identity theft, or for more information, write: Consumer Forum, P.O. Box 486, Brewer ME 04412, or e-mail contacexdir@live.com.