When is the best time to trade in or sell my car?

Generally, sooner is better, because most cars lose value over time and mileage keeps climbing. Selling before a big milestone, like 100,000 miles, before major scheduled maintenance, or before the warranty expires can help. Seasonal demand matters too: convertibles often sell better in spring, and all-wheel-drive vehicles before winter. Many people also time a trade around when they've built positive equity in their loan. Check current offers rather than relying on old estimates.