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So, Liquidity Services, the operator of liquidation.com, became a major (though not exclusive) handler of Amazon’s American liquidations. The company calls dealing with returns “the reverse supply chain”—a part of the retail business that has been growing in importance as online shopping becomes more popular. Liquidity Services now has 3,357,000 registered buyers on its various liquidation websites. In the past fiscal year, it sold $626.4 million worth of stuff.

Amazon represents a growing chunk of Liquidity’s business. In its most recent SEC filing, the company disclosed that it spent approximately $33.7 million on Amazon liquidation inventory, which it then turns around and sells for maybe 5 percent of the supposed retail value. And, assuming the company is trying to turn a profit, it must buy the inventory for a fraction of that. Doing the rough math, we’re talking about inventory that once had a collective value reaching into the billions, before it landed in some box on a doorstep.

Of course, once people do buy all these unwanted goods, they rearrange them into more profitable configurations. It seems so easy: Sort the still-good stuff from the broken objects, the trash, the worthless, and then post that stuff to Amazon or eBay. Who couldn’t sell $4,000 worth of stuff for more than $200?

My colleague Alana Semuels demonstrated in her story on the proselytizers selling get-rich-quick classes about retailing products on Amazon that the lure of the high-margin, online business is nearly irresistible. This is a variation on that hustle: Buy liquidation, sell high. This idea has won serious viewership for some YouTubers. It’s become a micro-genre on the video service, where different personalities unbox dozens of things and oooh and ahhh at how much money they are worth relative to what they paid for the box of stuff.

Read: How to lose tens of thousands of dollars on Amazon

YouTuber Safiya Nygaard got 12.6 million views for her unboxing of a liquidation pallet. YouTuber Kristofer Yee racked up 2.7 million views with a similar video. Another YouTuber, Randomfrankp, got 1.8 million. There’s an undeniable appeal to watching someone go through a whole bunch of strange stuff on camera. And these videos appear to have driven a noticeable spike of interest in liquidation on YouTube.

The implication in most of the videos is that the value of what’s in the box far exceeds the cost. Of course, two Yahoo reporters did it for themselves and got soaked. There’s a difference between something having a suggested retail price of $40 and actually getting someone to pay you $40 for it. The exchange value of most of these items is incredibly low outside the retail context in which they were purchased.

A level-headed Flint, Michigan, liquidation reseller named Walter Blake Knoblock offered a more realistic assessment in a live video he posted last year. He proffered five rules for Amazon pallets. The first? “Don’t expect it all to be good.” “ Don’t get discouraged if you’re halfway through your pallet and it’s all trash,” he said. In his business, it’s typical to throw away a third to half of everything.