20 Questions to Ask When Buying a Used Car (2026 Checklist)

Short answer: Ask the seller key questions, but verify every answer with data. Enter the reg on CarCostCheck for a free check that verifies mileage, MOT history, reliability, and running costs. The £4.99 premium report verifies finance, stolen status, write-off history, and keepers. Never rely solely on what the seller tells you.

Before You View: Questions to Ask (and Verify)

1. "What is the registration number?"

Why: You need this to run your checks. Any seller who refuses to share the reg before a viewing is a red flag.

Verify: Enter the reg on CarCostCheck immediately. The free report tells you more about the car than the seller will.

2. "What is the current mileage?"

Why: Mileage directly affects value and remaining component life.

Verify: The free CarCostCheck report plots every MOT mileage reading. If the seller's claimed mileage does not match the trajectory, the car may have been clocked.

3. "Is there any outstanding finance on the car?"

Why: If there is, the finance company can repossess the car from you after purchase.

Verify: The £4.99 premium report checks the Experian database. Do not rely on the seller's answer, as they may not know or may lie.

4. "Has the car been in an accident or written off?"

Why: Accident history affects value by 20-50% and may indicate structural compromise.

Verify: The premium report shows write-off categories. The MOT history may show post-accident advisories.

5. "Why are you selling?"

Why: The answer gives context. "Upgrading" is normal. "It keeps breaking down" is obviously bad. Evasive answers warrant extra scrutiny.

Verify: The reliability score and MOT failure pattern may explain why the seller wants rid of it.

At the Viewing: Questions to Ask

6. "Is the V5C in your name at this address?"

Why: If the V5C is in someone else's name, the seller may not have the legal right to sell the car.

Red flag: "It is in the post" or "my mate is selling it for me."

7. "Can I see the full service history?"

Why: A stamped service book with consistent entries shows the car has been maintained.

Verify: Cross-reference service book mileage entries with MOT mileage readings on your CarCostCheck report.

8. "When was the timing belt last changed?"

Why: If the car has a timing belt (not chain), replacement is due every 60,000-100,000 miles and costs £400-800. A snapped belt destroys the engine.

Verify: Should be documented in the service history. If not, budget for it.

9. "Are there any known faults or things that need fixing?"

Why: An honest seller will disclose issues. Compare their answer to the MOT advisories in your report.

Verify: If the CarCostCheck report shows advisories the seller did not mention, ask about them specifically.

10. "Has any bodywork been repaired or repainted?"

Why: Professional-looking repairs may be hiding accident damage.

Verify: Check panel gaps and paint consistency during your physical inspection.

11. "Can I see the car start from cold?"

Why: Cold starts reveal problems that disappear once the engine is warm. Blue smoke (worn seals), white smoke (head gasket), rough idle (injectors), and warning lights.

Red flag: The seller has already warmed the car up before you arrive.

12. "Can I take it for a test drive on different roads?"

Why: You need to test at varying speeds, on bumpy roads (suspension), and with braking (should stop straight).

Red flag: Seller insists on a short route or specific roads only.

13. "Are both keys available?"

Why: A replacement key for a modern car costs £200-500. Only one key may indicate the car was stolen or repossessed.

14. "When is the MOT due?"

Why: A car with an MOT expiring next week may need work to pass. You already know the answer from your CarCostCheck report.

Verify: The free report shows the exact MOT expiry date.

15. "How long have you owned it?"

Why: Short ownership (under 6 months) combined with selling at a loss can indicate problems discovered after purchase.

Verify: The premium report shows keeper change dates.

After the Viewing: Final Checks

16-20: Pre-Purchase Final Steps

Frequently Asked Questions

What Makes CarCostCheck Different

CarCostCheck is not just a cheaper version of HPI. It is a fundamentally better product that happens to cost 75% less. Here is what you get that HPI does not offer at any price:

• Real-time market valuation from £2.99, powered by over 650,000 live UK dealer listings. See what your car is actually worth in your local area, how quickly similar cars sell, and how the price compares nationally.
• Estimated vehicle lifespan: Our AI model analyses over 100 million data points to predict how many years the car has left and the probability of it being on the road in 12 months.
• Insurance costs by age: See estimated annual premiums for drivers aged 20, 30, 40, and 50. Budget before you buy.
• Running cost breakdown: Annual fuel, road tax, MOT, predicted repairs, and total cost per month. All calculated for this specific car.
• Health score (0-100): A single number that tells you the overall condition of the vehicle based on MOT history, advisory patterns, mileage consistency, and maintenance trends.
• Common faults: Known issues for this exact make and model, drawn from real MOT failure data across thousands of vehicles.
• 12 free checks: Full MOT history, mileage verification, reliability score, running costs, fuel costs, insurance group, red flag alerts, common faults, recall check, ULEZ compliance, and more. All before you pay a penny.

The premium history check (£4.99) uses the same Experian database as HPI, AA, and RAC. You get identical stolen, finance, and write-off data. The complete bundle (history + valuation) is £6.99, still 65% cheaper than HPI's basic check.

Related Reading

• Buying a Car from a Private Seller: Essential Checks
• How to Negotiate a Used Car Price in the UK
• Used Car Scams UK: 10 Scams and How to Avoid Them