You found a 2018 Ford Focus on Facebook Marketplace for £9,000. Photos look right. Seller seems straight. You are driving over Saturday to view it.

Before you do — spend £20 on an HPI check. Of every line of advice anyone has ever given a UK used-car buyer, this single thing has the highest return on investment. A clean check is the cheapest insurance in motoring. A dodgy check is the £4,000 problem you avoided.

Here is what each finding on a UK HPI check actually means, and how to react.

What "HPI Check" Actually Means

"HPI" became a generic term for a vehicle history check the way "Hoover" became a term for vacuum cleaner. The original company is Cap HPI, but multiple providers offer similar checks: HPI Check (the original), AutoTrader Vehicle Check, RAC Vehicle Check, Motorway Vehicle Check, and free quick-checks via gov.uk for some basic items.

A full UK vehicle history check costs £15-25 and pulls data from:

  • DVLA (registration, V5C history, mileage records at MOT)
  • Police National Computer (theft markers)
  • Insurance industry shared databases (write-off categories)
  • Finance company records (outstanding HP / PCP)
  • Manufacturer recall databases
  • Number plate change history
  • Colour change history

The 5 Findings That Should Make You Walk Away

1. Outstanding Finance

This is the single most common nasty surprise. The seller still owes the finance company. If you buy the car, in many cases the finance company can repossess it from you — even though you paid the seller in full. UK law on this varies (innocent purchaser rules apply in narrow cases) but the safest move is: if there is outstanding finance, do not buy unless the finance company confirms in writing the debt is settled at the point of sale.

Real cost of ignoring: the entire purchase price plus legal fees. £9,000 down the drain.

2. Stolen Marker

If the car is recorded as stolen on the Police National Computer, you cannot legally own it. It will be seized when you tax it, MOT it, or have any contact with police (a stop-and-check, an accident report, anything). You lose the car and the money. The seller is committing a crime; you become collateral damage.

Real cost: the entire purchase price.

3. Cat A or Cat B Write-Off

UK insurance write-off categories matter:

  • Cat A — scrap only, must be crushed. Cannot legally be on the road. If you see Cat A on a check and the car is being sold to drive, walk away — something is very wrong.
  • Cat B — body shell scrap, but salvageable parts may be reused. The car itself cannot return to the road.
  • Cat S (Structural) — repaired structural damage. Can return to the road if properly repaired. Insurance and resale value permanently affected.
  • Cat N (Non-structural) — repaired non-structural damage (cosmetic, electrical). Can return to the road. Less price impact than Cat S.

Cat A or B = walk. Cat S = walk unless repair invoices are detailed and you have it independently inspected. Cat N = price should reflect 15-25% discount vs equivalent clean car.

4. Mileage Discrepancy

The check compares the seller's claimed mileage against the recorded MOT mileages over the years. If the recorded mileage at the 2022 MOT was 78,000 and the car is now being advertised at 65,000, the odometer has been wound back. Clocking is illegal and the car is worth a fraction of its asking price (and may have hidden mechanical wear consistent with the higher real mileage).

Real cost: paying for a 65,000-mile car you are getting a 95,000-mile car.

5. Multiple Colour or Plate Changes

Not always sinister, but worth asking about. A car that has been resprayed and re-registered with a personal plate, then re-registered again, sometimes signals identity manipulation. Ask why each change happened. A respray for cosmetic reasons is fine. A respray immediately after a previous keeper is a question to ask.

Findings That Are Less Serious But Worth Asking About

  • Multiple previous keepers in short succession — could be a problem car being passed on, or could be company fleet pool. Ask.
  • Recent import — UK V5C will show. Imported from Ireland post-Brexit may have VRT, VAT and customs implications you inherit. Imported from Japan or EU may be left-hand drive (rare these days) or have non-UK spec items.
  • Open recall — common, often cosmetic, but ask the seller to have the recall completed at the manufacturer dealer (free) before you collect.

What HPI Checks DO NOT Tell You

  • Mechanical condition. The check is paperwork, not a wrench in the engine. A clean HPI on a knackered engine is still a knackered engine.
  • Service history quality. The check confirms the V5C and mileage; it does not confirm the car was looked after.
  • Cash sales of repaired write-offs done outside insurance — sometimes a Cat S or N car is bought from auction, repaired, and sold without the buyer being aware of the category.
  • Future reliability. No check predicts the next breakdown.

This is why HPI is one piece of the puzzle, alongside: physical inspection (or paid pre-purchase inspection from an independent mechanic), test drive, service history review, and gut feel about the seller.

The 5-Minute Pre-Purchase Process

  1. Get the registration number (VRM) from the seller before viewing
  2. Use the free gov.uk vehicle enquiry for a quick check (tax status, MOT status, basic data — free, instant)
  3. Run a paid HPI-style check (£15-25) — Cap HPI, AA, RAC, Auto Trader Vehicle Check, etc.
  4. Look up MOT history at gov.uk/check-mot-history — free, every test, every advisory
  5. If everything checks out, drive over and inspect the car physically

Total cost: £15-25. Total time: 5 minutes. Saved cost when something is wrong: £4,000-£15,000.

If You Find a Problem After Buying

  • Stop driving the car
  • Contact Citizens Advice for next steps — they have specific guidance for stolen, written-off and finance-encumbered vehicle purchases
  • If you bought from a dealer (not private), the Consumer Rights Act 2015 gives you 30 days to reject a faulty vehicle
  • Report stolen vehicles to police immediately — Action Fraud or 101
  • If finance is outstanding, contact the finance company directly — they will tell you the settlement figure and your options

Sources & Further Reading

Why We Care

My Mekavo is free for UK car owners. Once you buy a car that passed the HPI check cleanly, log every service, every MOT, every receipt — so when you sell, the buyer can run their own HPI check AND see your transparent ownership history. Trust both ways.