Get an after-the-purchase markdown. If the item you bought goes on sale within the week or the month, many stores will pay you back the difference. Keep your receipts! Some retailers offer a price guarantee over 100% – that means if you find the item cheaper anywhere else, prove it to the retailer and they’ll beat that price. Use tools like Slice or paribus.co that scour the receipts in your inbox and then claim your discounts automatically if they price drops.