I want to buy a designer purse that I saw at a thrift store. How can I tell if the purse is genuine or a knockoff? Are there any telltale signs to look for?
—Heather E., Los Angeles

As much as I want to say there's an easy way to tell—insisting on original receipts from an eBay reseller, relying on authenticity cards—there's really only one surefire way to shop smart. And that is, unfortunately, to stick only to reputable retailers.

By "reputable" I mean reputable. Not "reputable where I'm from," or "Mom's pool boy's cousin owns this place, so I know it's good." I mean a name that carries respect clear across the country—either the brand boutique itself or a well-known department store. If you buy your Dolce & Gabbana "Miss Sicily" bag from Nordstrom, you won't own a knockoff.

Period.

If you refuse to do things the legit way, chances are very high that you'll end up with a knockoff, and not necessarily an inexpensive one. Yes, usually a stiff construction, shoddy stitching or poor grammar or spelling are all dead giveaways, but those traits come nowhere near close enough to protect you from a bad purchase.

Now, for the record, a Louis Vuitton spokesman once told me that you can always visit your ever-approachable local Vuitton salesperson to authenticate your bag—if we're talking Vuitton, of course. I was informed that you should fret not if the salesperson wishes to spirit that handbag away to glittering Paris; sometimes that has to happen in order to assure authenticity, I was told. Besides, just knowing that your purse is visiting the birthplace of couture should keep you plenty enthralled until it returns.

So, the lesson for today? Better safe than sorry. Good luck, dear.

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