Personal finance clarity

Car Loan

Model an auto loan with tax, trade-in, and negative equity — or compare offers
Vehicle & Financing
Monthly Payment
$702
Vehicle price$35,000
Sales tax (7%)$2,450
Dealer / doc fees$600
Cash down– $3,000
Trade-in equity$0
Amount financed$35,050
Total Interest
$7,090
over 5 yrs
Out-of-Pocket
$45,140
$3,000 down + $42,140 payments

What actually determines your payment

Not the sticker price — the amount financed: price, plus sales tax and dealer fees, minus your down payment and trade-in equity. In most states you only pay sales tax on the price after the trade-in credit, which is real money people forget to count. The ledger shows every line so nothing hides in the paperwork.

Upside down on your trade-in?

If you owe more on your current car than it’s worth, that shortfall — negative equity — usually gets rolled into the new loan. You start the new loan owing more than the car costs. The calculator flags it in red, because it’s the single most expensive thing to sleepwalk into at a dealership.

Lease vs. buy, in plain terms

A lease payment covers the car’s depreciation during your term plus a finance charge (the “money factor” — multiply by 2400 to see the hidden APR). Buying costs more per month but builds equity you keep. The comparison here uses net cost to drive: everything you pay, minus the equity you walk away with. That’s the only fair way to compare them.

FAQ

Are 72- and 84-month car loans a bad idea?

They buy a lower payment with much more interest and years of being underwater. The calculator warns you and shows the exact cost of the longer term.

How much car can I afford?

Work backwards: the Affordability mode turns a monthly payment into a maximum vehicle price, after tax, fees, down payment, and trade-in.

What's a money factor?

A lease's interest rate in disguise. Money factor × 2400 ≈ APR. If the dealer quotes 0.00300, you're paying about 7.2%.