New vs used car: compare depreciation, repairs, financing, and resale
2026-07-19
The useful new-versus-used question is not which category has the lower sticker price. It is which exact vehicle leaves you with the lower cost and manageable risk over the years you will actually keep it. A five-year answer can reverse at year three because depreciation, loan payoff and repair exposure do not move at the same speed.
This model therefore avoids a single market-average verdict. It compares two written offers, accrues interest only while you own each car, and publishes both an expected used-car repair case and the full-repair downside.
Direct answer
A used car is not automatically cheaper and a new car is not automatically safer financially. Compare both over the same holding period: transaction price and fees, interest accrued while you own it, expected repairs, and resale value. In this five-year example the used car costs about $26,735 versus $26,774 for the new car—a difference of only $39. If the modeled $5,000 major repair actually occurs, used-car cost rises to about $30,235 and the new car is lower by roughly $3,461.
Inputs to collect
- Actual out-the-door price for each car, including dealer and government fees
- Down payment, APR and loan term for each offer—not just the monthly payment
- Planned holding period and the balance still owed when the car may be sold
- Routine maintenance and repair budget for each car
- Cost and evidence-based probability of one major used-car repair
- Conservative resale value at the end of the same holding period
- Vehicle-history report, open-recall check, warranty scope and independent inspection findings
Formula
TCO during holding period = purchase price + transaction fees + interest accrued during holding + routine repairs + (major-repair cost × probability, for the expected case) − resale value. Loan balance at sale is shown separately because sale proceeds must first retire that debt. Downside used-car TCO replaces the probability-weighted repair with the full repair cost.
Worked example
Hold both cars for five years. New: $36,000 price, $3,000 fees, $6,000 down, 4.9% APR for 60 months, $500 repairs per year and $19,000 resale. Interest is about $4,274 and TCO is $26,774. Used: $24,000 price, $2,500 fees, $6,000 down, 8.5% APR, $1,200 repairs per year, $12,000 resale, plus a 30% chance of a $5,000 major repair. Interest is about $4,735 and expected TCO is $26,735—only $39 lower. If the full repair occurs, used-car TCO is $30,235.
Sensitivity check
| Scenario | Changed input | Result |
|---|---|---|
| Used-car financing improves | Used APR falls from 8.5% to 5.5% | Used expected TCO about $24,994; used lower by about $1,780 |
| Used-car resale disappoints | Used resale falls from $12,000 to $9,000 | Used expected TCO about $29,735; new lower by about $2,961 |
| New-car discount | New transaction price falls by $2,000 | New TCO about $24,774; new lower by about $1,961 |
| Sell after three years | New resale $26,000; used resale $16,500 | New about $18,040 vs used $18,994; new lower by about $954, with loan balances still due |
| Major used repair occurs | Replace 30% expected value with the full $5,000 repair | Used downside TCO about $30,235; new lower by about $3,461 |
Compare your two car offers and repair scenario
Limitations
- The repair probability is a scenario, not a forecast. Base it on an independent inspection, model-specific service history, mileage and documented condition.
- History reports can reveal title, mileage or damage records but do not replace a mechanical inspection. Confirm open recalls separately and get every dealer promise in writing.
- Resale value is uncertain and can dominate a short holding period. Use a conservative offer or multiple current trade-in quotes, then test a lower value.
- Insurance, fuel or electricity, tax and registration are excluded only when they are genuinely similar between the two candidates. Add their differences for a full ownership comparison.
- This is an educational cash-flow model, not a vehicle, credit, legal or safety recommendation.
Sources and verification
- Federal Trade Commission — Buying a Used Car From a Dealer
- Federal Trade Commission — vehicle history, NMVTIS and open-recall checks
- Consumer Financial Protection Bureau — compare APR, amount financed, finance charge and total payments
Last verified:
New vs used car holding-cost calculator
Enter two real out-the-door offers. The expected used-car result probability-weights one major repair; the downside result assumes you pay it in full.
- New-car holding cost
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- Used expected holding cost
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- Expected cost difference
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- New interest during holding
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- Used interest during holding
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- New price minus resale
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- Used price minus resale
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- New routine repairs
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- Used expected repairs
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- Used cost if major repair occurs
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- New loan balance at sale
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- Used loan balance at sale
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- New monthly payment
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- Used monthly payment
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Educational estimate. Inputs stay in your browser. Verify price, loan, warranty, vehicle history, inspection, repair and resale independently.
Start with out-the-door price and a financing worksheet
Ask each seller for the complete out-the-door price. Then compare the loan’s APR, amount financed, finance charge, total of payments and required products. The CFPB warns that an affordable-looking monthly payment can come from a longer term and higher total cost. Enter the actual down payment and term so the calculator can also show the payoff still due if you sell early.
Down payment changes financing and liquidity, but it does not make the car economically cheaper: the purchase price is still paid. That is why the TCO formula counts price once and adds only interest, while the monthly payment remains a cash-flow output.
Used-car due diligence changes the repair scenario
The FTC Buyers Guide states whether a dealer offers a warranty or sells the vehicle as is. Read it alongside the written contract, obtain a vehicle-history report, check open recalls and pay for an independent pre-purchase inspection. A history report can reveal recorded title, mileage or damage events but cannot see a current leak, worn suspension or intermittent electrical fault.
Turn the inspection into numbers: scheduled work due during the holding period, an annual wear budget and one plausible major repair. Do not claim that every used car has a 30% failure probability; 30% is only the editable stress assumption in this example.
Resale and holding period can flip a narrow result
The base result differs by only $39, so it is a tie for practical decision-making. Lowering used-car resale by $3,000 makes the new car about $2,961 cheaper; paying the full major repair makes it about $3,461 cheaper. Conversely, a 5.5% used-car loan makes the used option about $1,780 cheaper.
For a three-year exit, obtain resale quotes for the age and mileage you expect and inspect the loan balance. A positive resale value does not mean positive cash back if the payoff is higher. Test the holding period you can realistically commit to, not the longest period that makes one offer look good.
Add costs that differ between the two exact cars
If insurance, fuel economy, registration or taxes differ materially, add those differences in a full vehicle total-cost comparison. Common costs can be omitted only when the candidates truly share them. Reliability, crash safety, utility and warranty coverage remain decision criteria even when they do not fit a single dollar estimate.
General educational estimate, not a vehicle, loan, legal or safety recommendation. Verify documents, condition, recalls, insurance and payoff before signing.