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Buying & Selling

Buying a Used Car: Complete Guide

A thorough guide to buying a used car in the UK, from researching the history to completing the paperwork safely.

Before You View: Research

  • Run an HPI check (£20–30), confirms outstanding finance, insurance write-off status, stolen status, mileage discrepancies, and number of previous owners. Worth doing on any private purchase.
  • Check the MOT history for free at gov.uk/check-mot-history, look for recurring advisories (signs of ongoing issues) and any unexplained gaps.

Documents to Check

  • V5C (logbook), Must be present. Check the name and address matches the seller and the VIN on the car. If the seller isn't on the V5C, ask why.
  • Service history, Stamped book or receipts. Continuous history adds value and proves the car has been maintained.
  • Current MOT certificate, Cross-reference the mileage on the certificate with the dashboard.

Exterior Inspection

  • Panel gaps, Stand back and look along the car. Uneven gaps between panels suggest accident repairs or poor quality bodywork.
  • Paint shades, Look for panels that don't quite match (different sheen, slight colour difference), sign of repair.
  • Rust, Check wheel arches, sill edges, door bottoms, and around windows. Surface rust can be cosmetic; bubbling paint indicates deeper structural rust.
  • Tyres, Check tread (1.6mm legal minimum, use the 20p test), tyre pressures, and look for cuts, bulges, or uneven wear.
  • Lights and windscreen, Check all lenses are intact. Any chip or crack wider than 10mm in the driver's direct view zone fails the MOT.

Interior Inspection

  • Seat condition, Should match the claimed mileage. Heavily worn driver's seat on a low-mileage car is a red flag.
  • Pedal wear, Same logic. Worn pedal rubbers suggest higher mileage than stated.
  • Smell, Damp or musty smell suggests water ingress. Sweet smell could be coolant leak.
  • Warning lights, Start the engine and check all warning lights illuminate on start-up then go out. Any lights that remain on after start-up need investigating.
  • Electronics, Test all windows, mirrors, air con, infotainment, USB ports, and heated seats if fitted.

Under the Bonnet

  • Oil level and condition, Should be between MIN/MAX. Milky or frothy oil cap = head gasket failure. Walk away.
  • Coolant level, Check when cold. Should be between MIN/MAX.
  • Signs of leaks, Look for oily patches on engine components, wet areas, or fresh sealant (hiding a recent repair).
  • Belts and hoses, Cracked or perished rubber is a sign of age/neglect.

Test Drive (15–20 Minutes)

  • Cold start, engine should start cleanly with no excessive smoke
  • Check steering doesn't pull to one side on a straight road
  • Test brakes, should feel firm, stop in a straight line, no judder or noise
  • All gears should engage cleanly (manual: no crunching; automatic: no jerking or hesitation)
  • Clutch should bite roughly in the middle of travel (not right at the floor or top)
  • Listen for unusual noises, knocking, rumbling, squealing
  • Check the temperature gauge reaches and stays at normal operating temperature

Red Flags, Walk Away

  • Seller can't produce the V5C, or it's in a different name
  • Outstanding finance on the HPI check
  • Mileage discrepancies between MOT records and dashboard
  • Milky oil cap (head gasket)
  • Seller is pushy, evasive, or won't allow a test drive
  • Price is significantly below market value for no clear reason
  • Seller insists on meeting at a public place (may not be their car)

Pre-Purchase Inspection

For higher-value cars, consider a pre-purchase inspection by the AA, RAC, or a mobile mechanic (£100–200). They will check for hidden faults that a layperson might miss.

Completing the Purchase

  • Pay by bank transfer only, no cash for large amounts (harder to trace), no crypto
  • Get a receipt confirming price, date, seller details, and car details
  • Complete the V5C change of ownership section and post it to DVLA (or do it online)
  • Set up insurance before driving the car