Two prices for every car
There is a trade price and a retail price, and the gap between them is the entire used car industry. Fleets, lease companies, insurers and dealers dispose of stock at wholesale auctions largely closed to the public; dealers buy there, prepare and warrant the vehicle, and sell at retail.
Understanding which price you are being offered is the most useful thing a private seller can know. Part-exchange is a trade price with a retail conversation wrapped around it, and the difference on an ordinary family car is routinely £1,000–£3,000.
Depreciation is the dominant cost
A new car typically loses a substantial share of its value in the first three years — commonly 40–60% depending on model. That loss dwarfs fuel, servicing and insurance combined for most owners, and it is the reason the three-to-four-year-old car is the value sweet spot of the market.
Depreciation is not uniform. Models with strong residuals hold value because of demand, reliability reputation and controlled supply; models pushed heavily into rental fleets or sold with large discounts depreciate faster, because the wholesale market is flooded with them at three years old.
The pandemic distortion
Semiconductor shortages cut new car production sharply from 2021. With no new supply, used values rose — some cars were worth more at a year old than they cost new, which had essentially never happened at scale before.
The unwind from 2023 was painful for anyone who bought at the peak, and particularly for used electric vehicles, where values fell sharply as new EV prices were cut, battery degradation concerns persisted and supply from lease returns increased.
Finance is the real product
Most UK new and used car transactions are financed, commonly through PCP, where the customer pays for the depreciation over a term and hands the car back or refinances a balloon payment. This makes monthly payment, not price, the number most buyers negotiate — which is precisely why dealers prefer to discuss it.
The FCA's review of historic motor finance commission arrangements has led to substantial redress consideration across the industry, and it is a live issue for anyone who bought on finance in the relevant period.
What to check
Outstanding finance is the single biggest trap in private purchase: a car with finance owing is not the seller's to sell, and can be repossessed from an innocent buyer. A provenance check covering finance, insurance write-off status, stolen markers and mileage discrepancy costs a few pounds and is never optional.
How you would actually trade it
Selling privately gets the best price and takes the most effort; the online buying services sit between trade and retail and are quick but cheaper. Get quotes from several before accepting a part-exchange.
Buying privately is cheapest and carries the least protection — private sales need only be "as described", with no right to a refund for faults. Buying from a dealer brings the Consumer Rights Act, including a 30-day right to reject a faulty vehicle.
Always: HPI-style provenance check, MOT history from the government service (free, and it shows advisories and mileage at each test), service history, and an independent inspection on anything expensive.
What goes wrong
- Depreciation is relentless and front-loaded.
- Outstanding finance on a privately bought car can cost you the car.
- Clocking and cloning. Mileage fraud and cloned identities remain common.
- Write-off history materially reduces value and may be undisclosed.
- EV-specific risk. Battery health is the asset, and residuals have been volatile.
- Private sales carry minimal consumer protection.
This entry describes how a market works. It is not a recommendation, a price forecast, or advice about whether this belongs anywhere near your money. How entries are written.