Just like selling your house, the cheapest way to add value to a car is to clean it thoroughly. Seems obvious, but we don’t always notice the grime on something we see every day. Also sprinkle baking soda on the carpets and cloth seats, then vacuum it up to remove odours you might not smell but potential buyers will. Arm & Hammer recommends waiting at least 15 minutes before turning on the vacuum, “or longer for strong odours.” If you’re a smoker, that can mean letting it sit overnight – and not smoking in the car for at least a week. You can scrub your floor mats, but if they still look bad, replace them. Clean out the glove box, removing everything but the owner’s manual. While you’re cleaning the windshield, make sure the windshield wipers are in good condition and that they function properly. If they don’t, it’s a sign that other parts of the vehicle may also have been neglected.