Starting this week, Costco is making it easier to splurge on that mega grill, appliance, or other high-dollar item by teaming up with Affirm for a new "buy now, pay later" option. Shoppers can break up payments on purchases between $500 and $17,500, so it’s not for TP or trail mix, but perfect for high-dollar hauls. With a quick eligibility check, you can skip the credit card and still load up the cart. Just in time for summer upgrades!