Helmets are designed to protect you from one accident, and one accident only. Sometimes damage isn’t visible, so buy a new helmet to make sure you’re getting full protection.
Child car seats
Like helmets, car seats are really only meant to protect in one accident. But damaged car seats are common; a survey found that one in ten have been in an accident. Plus, car seat technology improves each year.
If they’ve been in an accident, tires are likely to be unstable and unreliable. Make sure you can get an accurate history.
Wet suits and swimsuits
Personal products that hug your body are technically safe if you wash them in hot water... and still we're cautious. But constant changes in water pressure also wear out swimwear faster than regular clothing, so it's likely a used wetsuit or swimsuit will tear.
With bed bugs infesting homes in record numbers, chances are the critters could lurk in any used mattress. You might also end up sleeping with other people’s mold, mites, bacteria, and bodily fluids (yuck!).
Scores of crib recalls, as well as changing safety standards, make it hard to verify the safety of a used crib.
Laptops are more likely to be dropped, knocked around and spilled on, simply because they’re out in the world, while a desktop computer sits (mostly) safe at home.
It’s hard to determine how well TVs, DVD players, and other electronic devices have been cared for by their previous owners. Plus, technology changes so quickly that you can often get a better quality device. If you're buying refurbished devices directly from a manufacturer, you'll be covered by a warranty—but a random TV at a garage sale could be hit or miss.
Used shoes have been molded to their previous owner’s feet—and poorly fitting shoes will make you miserable, or you'll just never want to wear them.
Sheets and Pillowcases
Sure, you can wash them in hot water, but that might not protect against bed bugs.
While sanitation and cracks can be an issue, the real culprit is the chemical BPA that's present in most older bottles—and as of June 2012, the FDA no longer accepts that as safe. Go with new bottles to make sure you're getting the safest, most up-to-date bottles.
Worn plates, pots, and other cookware
Rust, flaky non-stick coatings, and chemicals that leach out are just a few of the safety problems you can run into with older cookware.
DVDs, CDs, and VHS tapes
Scratches have ruined many a DVD or CD—and VHS tapes can lessen in quality the more times they're played, and disintegrate over the years.
Just like mattresses and sheets, any upholstered furniture can be home to bed bugs, fleas, and spiders, as well as unknown odors and stains. Unless you're going to reupholster the piece, steer clear.
Clothes that require a tailored fit
It might look like it fits—until you put it on. Unless you can try something on, it's often not worth the money you'll spend on alterations.
You might want to quickly google the video game—manufacturers are now including codes for one-user only play, either for the whole game or special bonus sections.
Fragrance or makeup (new or old!)
The quality of both can lessen over the years (and yes, they do expire!). Even if an item is brand new in the box, skip it unless you can tell that it was recently manufactured.
Stuffed animals can be hard to send through the extra-hot cycle on a washing machine, and like mattresses and upholstered furniture, they can be full of creepy crawlies and other unsavory finds.
Blenders and other kitchen electronics
Blades and mechanisms can become dull and wear down over time, even if the machine looks fine on the surface.
Used running shoes are often devoid of the cushioning that runners need; stick with new shoes for the cushioning and fit that will protect knees, feet, and legs.
How's this for gross: Hats may contain remnants of hair products, sweat, or skin infections.