Customers often play a dangerous game in terms of refunds, and this game can ultimately result in some bitter consequences. In this case, a customer bought a designer item online, and when it arrived she sent a rude message to the seller, OP, demanding a full refund, threatening OP with filing a chargeback. The catch was Karen wanted OP to Venmo her the money, which is a huge, blaring red flag. OP said they would refund the money if the item was returned, per company guidelines. Karen discarded…