Sophia browses for clothes in a vintage clothing store and finds a jacket she wants to purchase. She bargains for a lower price for the jacket before leaving the store. Later, Sophia decides to sell the jacket on eBay and takes a few photos to try and make the jacket appear more fashionable. While she was able to buy the jacket for only $9, Sophia eventually sells the jacket on eBay for over $600 (the clip stops at $185). As the show progresses, Sophia continues to sell clothes and starts an online business called Nasty Gal, which is actually still in operation today. This clip is a prime example of arbitrage, where a person can purchase an item at a low price in one area (Sophia at the thrift store) and sell it for a higher price in a different market (Sophia on eBay). In a perfectly competitive market, the price differential should narrow, but because eBay has a much larger customer base, Sophia is able to buy items from the local thrift store and resell them later at a higher price.
Thanks to Elena Montenegro for the clip suggestion!