How we compute · Last reviewed 2026-09-14

TrothStone vs carwow

The difference in one line

carwow is a transaction broker: it collects your details, sends them to dealers, and dealers bid for your new-car business. TrothStone does not transact at all — it is a read-only research surface for the used market, scoring live listings for true cost of ownership. If you are buying new, carwow's funnel is the right tool. If you are buying used and want to know what a car actually costs to own, that is TrothStone.

carwow is a new-car deal-brokering funnel. TrothStone is a used-market analysis surface that never takes your details.

At a glance

	TrothStone	carwow
What it is	A research surface: browse, appraise, compare. No enquiry forms exist on the site.	A lead-generation platform for new cars: one enquiry, multiple dealers bid.
How it makes money	Nothing today. No lead fees are possible — there is nothing to generate leads for.	Fees from dealers for each qualified lead or sale.
Market covered	The used market: 417,146 live listings, 78 makes, 577 personal-lease deals, all scored.	New cars (plus part-exchange and sell-your-car services).
Data model	Aggregate statistics and per-listing derived scores, free and unauthenticated. No individual seller data is ever exposed.	Manufacturer list prices and dealer discount offers — offer-level, gated behind an enquiry.
Accuracy you can check	Published and reproducible: holdout RMSLE 0.161, MAE ~£1,770, with a 47-month forward backtest.	Discounts are whatever dealers bid; no model error is published.
What you give up	Nothing. No account, no cookies, no PII — the garage lives in your browser only.	Your contact details and buying timeline go to dealers.

carwow changed how the UK buys new cars by making dealers compete. TrothStone applies a different discipline to the used market: score everything for true cost of ownership, publish the model's error bars, and take no money from anyone. This page sets out the differences honestly — they are different products doing different jobs.

The starting point for any honest comparison is acknowledging what each product does well. carwow's dealer-bidding mechanic genuinely compresses the discount on a new car: the time-to-quote is fast, the offers are real, and a customer who would have paid list at a franchised dealer will usually pay less through carwow. If you are buying new and have decided on the model, carwow is the right next step. The reason this page exists is not to deny that.

What carwow does not do is analyse the used market. Their used presence is a sell-your-car funnel and a retail arm that competes on its own stock rather than the whole market. TrothStone's wedge is the analysis of the used market at scale: a corpus of scored listings against which any specific used car can be benchmarked for fair price, deal grade and true monthly cost. A buyer using both products would typically: shortlist a new model on carwow, then re-check the depreciation curve and three-year-old resale value on TrothStone before signing the PCP quote. The two products are complementary rather than competitive.

The data-handling posture is where the two diverge most sharply. carwow's product requires your details, your postcode, and a willing conversation with dealers. TrothStone requires none of that: no accounts, no cookies, no fingerprinting, no aggregate-only tracking that ties you to a session. The garage tool lives in your browser's local storage; the compare tool is client-side; the value-a-car tool runs an API call that does not log the plate you typed beyond a 7-day anonymous cache. The compliance posture is written into the operating model, not added on top of it. Both designs are coherent for what each product does — they just do very different things.

What this page is NOT

Not advice. Figures are model estimates for information only — not financial advice. Representative rates, not offers.
Not a comparison of every dimension. This page describes the structural difference between the two products, in plain English, with links to both sides.
Not UK-general. TrothStone scores the UK market only; carwow may cover more.
Not a sales pitch. TrothStone has no checkout, no lead forms, no paid placement. carwow's own site is the right place to evaluate their product.

Questions people ask

Is TrothStone an alternative to carwow?

For new-car discount brokering, no — carwow negotiates real dealer discounts on new cars and does it at scale. TrothStone covers the other half of the market: used. The two barely overlap, which is why this page exists rather than a head-to-head on the same job.

Does TrothStone sell my details to dealers?

No. There are no enquiry forms, no accounts, no cookies. Aggregate-only counting applies (page-path buckets, referrer domains); the compare and garage tools work entirely in your browser.

Which is better for used cars?

TrothStone, by construction — carwow's used presence is retail stock through its own channels, while TrothStone scores the whole live market (asking vs fair price, deal grade A–E, resale forecast, finance modes) for 417,146 listings. But see for yourself: every figure links to the methodology page.

See the difference on live data

Every claim above reduces to one habit: before you buy any car, check what the market says it is worth and what it costs per month to own. Browse 417,146 scored listings, or read how the numbers are computed.