Even good sites may have certain tools that aren't so hot. Some sites may make you poorer. And sometimes the problem is you.
Don't: Buy a car sight unseen on eBay.
Online auctions can be great for getting a deal on small items such as vases. But the consequences of making a bad choice are much greater for big-ticket purchases.
Instead: Most eBay sellers will let you hire a local mechanic to check out the car in person. Do it.
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