Thursday is Thanksgiving. Friday, we shop! Black Friday is a once-a-year opportunity to save in ways you’ve never saved before. Or, is it? Weren’t there ads for Black Friday deals last week? And won’t there still be sales on Saturday? And in January?

If you’re confused, that might be a good thing, particularly if it makes you slow down and carefully consider whether those bargains are bargains at all. According to Capital One Shopping, Americans are poised to spend in excess of $20 billion this Black Friday, including online shopping, even as the most recent analysis by Consumers’ Checkbook found that most of the 24 major retailers whose prices they analyzed made claims that were misleading consumers.

Since Black Friday isn’t really a single day, don’t feel compelled to shop on that day, says Maurie Backman, a personal finance writer with Motley Fool Money. She says you’ll be able to find similar prices throughout the holiday season and that you shouldn't be fooled by the discount retailers say they’re offering.

“If you haven’t been tracking prices throughout the season, you don’t really know what the original price was," Backman says. "There’s nothing stopping a retailer from saying 'I'm going to take this item that retails for $49.99, I’m going to put an $89.99 price tag on it, then I’m going to take a red marker and put a slash through that and sell it for $39.99.'”

Since there’s no law to prevent this, Backman says the best way to prevent being fooled is to start tracking prices for items you want or need months before the holiday season.

It's also common practice for retailers to partner with tech manufacturers to have special run products made specifically for Black Friday. Backman notes that the reason the 80-inch TV you want is suddenly $500 cheaper on Black Friday could be because the components are inferior. She urges consumers to compare the model and serial numbers of the sale item with those of the exact product they were looking at prior to Black Friday. If those don’t match, it’s a different product.

As for the Black Friday-only product, Backman says, “It’s not necessarily a bad buy." But she recommends asking yourself whether you want a less expensive price point for a product that might not perform similarly or last as long.

And do not be fooled by the “limited edition” ploy, she warns. Backman says that most “limited edition” products are simply packaged differently, and will almost certainly be available after Black Friday, after Christmas and even next year, though maybe in different packaging.

For those who aren’t shopping for the holidays, Backman recommends waiting until after Christmas to look for bargains. That’s when retailers start marking down products to clear their shelves of the previous year’s goods and when people start returning unwanted gifts. The latter are usually in perfect condition but end up discounted due to space or packaging issues, sometimes as minor as a dented box. This goes on through late December and into January.

Finally, Backman says that if you do go shopping, don’t feel compelled to buy products you don’t need just because they’re discounted.

“If you see a toaster oven that usually sells for $50 on sale for $30, and you buy it but you don’t need it, you’re not saving $20. You’re spending $30,” she says.

Backman adds that if you head into a store for a specific few items and the store doesn’t have them, “You didn’t fail Black Friday if you leave empty-handed!”