If you need advice, buy from a store with staff that can help you choose products that will serve you best, help you get started using new stuff, and help solve any problems. You also want low prices. Unfortunately, we found the lowest prices are mostly offered by online-only retailers; if you need a store with personnel that can offer solid advice, you might have to pay more to get it.

Which Stores Offer the Best Advice and Service?

When discussing options with salespeople at stores or reading product descriptions while shopping online, it’s okay to maintain a degree of skepticism. Remember, it’s a salesperson’s or website designer’s job to sell you merchandise that the store actually carries, and the store makes more when you spend more.

Our Ratings Tables show how computer outlets were rated by consumers we surveyed, primarily Checkbook and Consumer Reports subscribers but also other randomly selected consumers we invited to participate.

Our survey asked consumers to rate computer stores they had used “inferior,” “adequate,” or “superior” on several questions, such as “advice on choice and use of products,” “reliability (standing behind products, delivering on time),” and “overall quality.” For each store or chain that received at least 10 ratings, our Ratings Tables show the percentage of surveyed customers who rated it “superior” (as opposed to “inferior” or “adequate”) on each question.

For large chains, we report scores for individual stores, plus ratings submitted by consumers in the seven metro areas where we publish Checkbook.

Click here for further discussion of our survey and other research methods.

As you can see, some stores received very high marks from their surveyed customers for important aspects of service. But others scored dreadfully low. The range of scores for our question on stores’ “overall quality,” for example, ranged from less than 40 percent to more than 90 percent.

The best way to find out whether a product really meets your needs, of course, is to try it. Many stores offer one-month trial periods for hardware, which enable you to return products if you don’t like them. Stores have much less liberal return policies for software. Since policies vary from company to company and from product to product, find out how much time you have, and ask specifically about restocking fees that may apply if you return a device after you’ve opened the box.

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Be Careful When Buying Used

Because so many of us nerds trade up to get the latest, greatest devices, the secondhand electronics market is ripe for low-price picking. Although you can save a lot buying used tech vs. new, a lot of the secondhand stuff still comes with big price tags, which means the stakes are often higher than, say, nabbing a $10 tennis racket. And for computers, smartphones, TVs, and the like, it can be really difficult to determine if your deal involves a defective product.

So be careful who you buy from. We’d avoid private sellers unless you know them or someone who will vouch for them.

Stuff that was returned because the buyer wanted something else is fine; in theory, that’s the same as buying new, but the box or packaging was unsealed.

Next-best are products refurbished by their manufacturers. You can still run into trouble, but most of these deals come with warranties and tech support. For example, Apple offers a one-year warranty on its refurbished phones, as does Samsung for its certified pre-owned phones. Dell offers a 100-day limited warranty and a 30-day guarantee on its refurbished machines. We’d happily buy under one of these plans, especially if it’s a gift for one of our accident-prone kids.

The problem is the latest models are rarely available used; you’ll have to settle for saving by buying something manufactured a couple digital generations ago.

While we think refurbished stuff sold by manufacturers is probably fine, we wouldn’t buy secondhand items from other (even well-known) retailers. You just can’t know where they got their products, or what (if anything) was done to refurbish them. Some stores are hawking items that were returned because they were defective; the store or manufacturer has (hopefully) repaired them and then dumped them onto the secondary market. We’d rather buy something that was never defective.

If you’re thinking about buying from a retailer offering used stuff, read the fine print on your returns rights, guarantees, and warranties.

Click here for more advice on buying secondhand merchandise.

Don’t Buy Optional Extended Warranties

Most retailers will urge you to buy an extended warranty. These plans are profitable for the stores, and salespeople get a piece of the action, too. We recommend against buying them.