You may know that buying on Amazon.com doesn’t necessarily mean you’re buying from Amazon.com. More than one million third-party merchants list goods on the site through a program called “Amazon Marketplace,” generating $175 billion in sales last year, about 70% of Amazon’s overall sales.

Most Amazon Marketplace sellers are honest, but scams such as counterfeit goods and never-delivered purchases are on the rise. Buyers must watch out for three subtle signs that a Marketplace seller should be avoided…

Ultralong delivery times. Delivery dates several weeks in the future let scammers make as many sales as possible before buyers realize something’s amiss. Or long ship times might mean that the item is shipping from abroad, increasing the odds that it will be lost or damaged.

A “Just Launched” tag by the seller’s name. Some scammers launch new Amazon accounts frequently, abandoning their older accounts when bad reviews roll in. Other “Just Launched” sellers are honest but inexperienced and error-prone. 

Phony raves about the seller’s goods. Be wary if most positive reviews of an item are only a few sentences long…are so generic that they could refer to anything…are in broken English…and/or are “unverified,” meaning that the reviewer didn’t buy the product on Amazon. 

If you think you might have been scammed: If an item doesn’t arrive, is not as described or you suspect it’s fake, try to contact the seller, explain the problem and ask for a refund. If this fails, file a claim with Amazon—locate the purchase in your list of orders, click “Problem with order” and follow the directions to request a refund—Amazon almost always sides with buyers over Marketplace sellers. If that fails, contact the issuer of the credit card you used to make the purchase, explain the situation and request a “chargeback.” ­