If you buy something online and it never shows up, you might be a victim of this type of scam. Scammers will often “sell” stuff on sites like Craigslist and Facebook Marketplace, or set up fake online storefronts, take your money, then never deliver what you ordered. 
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Online purchasing scams often involve purchases and sales on classifieds websites and other direct seller-to-buyer sites. Scammers may pretend to purchase an item only to send you a bogus check and ask you to refund the “accidental” overpayment. In other cases, the scammer will pretend to be a legitimate online seller but never deliver the goods