This one mistake could cost you nearly $3,700 on your next car purchase. Let's go through a real scenario. See if you can spot where people go wrong. 2026 Toyota Highlander XLE Financed amount: $47,000 Interest rate: 6.97% (current average for a well-qualified buyer) 60 months (5 years) Monthly payment: $930 Total interest paid: $8,800 Total amount paid: $55,800 72 months (6 years) Monthly payment: $801 Total interest paid: $10,672 Total amount paid: $57,672 84 months (7 years) Monthly payment: $708 Total interest paid: $12,472 Total amount paid: $59,472 The difference between a 5-year and 7-year loan on this vehicle: $3,672 in extra interest. And there's the mistake. People will take the lower monthly payment, even though it means paying more over the life of the loan. I know it doesn't make sense to you and me. But I've seen it happen. And I would never recommend it. And at 6.4% over 84 months on a vehicle that depreciates as fast as a Highlander does, you'll be underwater on that loan for a big chunk of the time you own it. 60 months or fewer is where you want to be. 72 months can make sense if the interest rate is low enough to justify it. 84 months is a trap.