The dealership smells like floor wax and expensive coffee. Leo sits across from a salesman named Marcus, who is currently sliding a four-square sheet across the desk.

He pays an extra $2,000 today. His payment drops to $440.

No extra money upfront, but $500 a month for 60 months.

"Think of it as a trade," Marcus says. "You pay a little more today—an upfront fee or a larger down payment—and in exchange, the bank drops the interest rate for the life of the loan. You’re essentially prepaying the interest to save money every month." Leo pulls out his phone calculator. He sees two paths: