Compare the out-the-door car price, not just the monthly payment

Two financing offers are comparable only when you understand the complete vehicle transaction behind each one. Ask for an itemized, written out-the-door price before negotiating a monthly payment.

What goes into the total?

Start with the agreed vehicle selling price. Add the taxes, title, registration and mandatory transaction fees quoted for the purchase. Examine documentation charges and any protection products or other add-ons. Ask which charges are optional. State and local treatment varies, including whether a trade-in affects taxable value, so use the actual numbers in your quote rather than a national percentage.

Keep trade-in value and old debt separate

If a dealer offers $12,000 for your old car and you owe $8,000 on its loan, your trade-in equity is $4,000. If you owe $14,000, you have $2,000 of negative equity. Rolling that debt into the new loan does not erase it. Check the trade allowance and payoff separately on the written deal.

The calculator uses net trade-in equity to estimate the cash or amount financed for a purchase. Because the existing car is a separate asset, the displayed estimated cost does not itself value your old car as a separate economic cost; compare routes using the same trade-in assumptions.

Ask how rebates interact with the loan

A manufacturer may offer a low promotional financing rate or a cash rebate that cannot be combined with that rate. A lower interest rate can still be the more expensive full offer if it requires you to pay more for the car. Enter the cash or bank rebate and dealer financing rebate separately, according to the written terms you qualify for.

Simple checklist

• Request an itemized vehicle selling price and all taxes and fees.
• Ask whether add-ons are optional and have unwanted items removed before signing.
• Get your trade-in allowance and payoff balance in writing.
• Request the APR, contract rate, amount financed, length, total payments and any rebate restrictions.
• Check that the terms match the paperwork you are about to sign.

Sources: FTC guidance on financing or leasing a car and CFPB auto loan resources.

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Reviewed September 2026 · Independent educational comparison