The monthly payment is not the cost
The FTC specifically advises buyers to focus on total cost, not only the monthly payment. A lower payment can come from a longer loan term and can increase the amount paid overall.
| Replacement cost | Easy to miss? | Why it belongs in the comparison |
|---|---|---|
| Depreciation | Yes | Often one of the largest economic costs of owning the replacement. |
| Taxes and one-time fees | Yes | They occur because you replace now rather than keep the current car. |
| Financing | Often | A low monthly payment can hide interest and a long loan term. |
| Maintenance and repairs | Sometimes | Newer does not mean zero maintenance forever. |
| Future resale value | Often | It offsets part of the replacement path at the end of the horizon. |
Once you have realistic values for these items, run the Car Repair vs. Replace Calculator rather than comparing the repair bill with a monthly payment.
For a repair-versus-replace decision, the question is not “Can I afford the payment?” It is “What does the replacement path consume over the period I am comparing?”
1. Depreciation
Depreciation is often one of the largest ownership costs of a replacement vehicle. AAA's ownership-cost framework treats depreciation separately from fuel, financing, maintenance, taxes, and other costs. For our calculator, what matters is the replacement's purchase price minus its expected value at the end of the comparison period.
2. Taxes and one-time fees
Sales tax, title, registration, document fees, and required dealer charges can make the real out-the-door price meaningfully higher than the advertised price. The FTC recommends getting the out-the-door price in writing before discussing financing.
3. Financing cost
Interest is not the same thing as the vehicle price. If you finance the replacement, include the interest expected during the comparison period. If you pay cash, do not invent financing cost; enter zero and treat any investment opportunity cost separately if it matters to you.
4. Maintenance and repairs do not disappear
A newer replacement may require less repair spending, but it still has maintenance costs. Compare realistic expected costs on both vehicles rather than treating the replacement as maintenance-free.
5. Future resale value
At the end of the comparison period, both vehicles still may have value. Ignoring that value distorts the result. Compare beginning and ending values over the same horizon.
6. Fuel or energy savings
If the replacement materially changes fuel or electricity costs, include the difference. Keep this assumption separate so a small fuel advantage does not accidentally justify a much larger purchase.
The calculator compares the major costs that change between keeping the car and replacing it.
Compare the full paths →What not to count twice
Do not include today's current-car value as though it were a new cash expense and also charge the full depreciation separately. Our model treats current value as an asset and measures the value consumed over the comparison period.
Quick answer
Replacement can absolutely be the better decision. Just make sure it wins after depreciation, fees, financing, maintenance, and future value are included—not merely because the monthly payment feels manageable.
Run the car repair-versus-replace calculator, then change the one or two assumptions you are least certain about.
Open the Car Repair vs. Replace Calculator →Sources and further reading
- Federal Trade Commission: Financing or Leasing a CarGovernment / primary
- Federal Trade Commission: Buying a Used Car From a DealerGovernment / primary
- NHTSA: Vehicle recall lookupGovernment / primary
- AAA: 2026 Your Driving Costs overviewAuthoritative reference
Dollar examples on this site are illustrative assumptions, not forecasts for a specific vehicle.
