Sliding into a car with worn-out seats takes the joy right out of driving. Keeping your interior clean costs a bit up front, but it protects your resale value down the line. If you want the best price on custom covers, shop during the slower winter months or around major holiday sales when auto shops and online makers drop their prices to move inventory.
You should always negotiate the price of the product and any installation fees before you even mention how you plan to pay. Financing is just a tool for spreading out the hit to your bank account, not a discount on the retail price. Let's look at the numbers and map out a clean way to handle the cost.
Remember that the 0% window is a hard deadline, not free money. If you still have a remaining balance when the 18 months are up, deferred interest or standard purchase APR will kick in on what is left, wiping out any savings you gained from timing your purchase right.