The Marker Never Leaves: How to Price Cat S Risk Without Getting Buried

Every few weeks a Cat S rolls onto a forecourt with a story attached. The seller has a folder of photos on their phone, a receipt from a bodyshop nobody has heard of, and a price that looks like a genuine gift. Sometimes it is. Most of the time it is a transfer of risk from someone who knows exactly what they are holding to someone who is hoping.

There is nothing wrong with buying a written-off car. Trade buyers do it every day and make decent money doing it. What separates a calculated bet from a trapped purchase is whether you have actually priced the three things that come with the marker, rather than just nodding at the discount and telling yourself the repair looks tidy.

What the marker actually means, briefly

Insurance write-off categories were overhauled in October 2017. The old Cat C and Cat D became Cat S and Cat N. Cat S is structural damage - the insurer decided the shell was hurt badly enough that repairing it was not economic for them. Cat N is non-structural, meaning the damage was cosmetic or bolt-on, but the repair bill still beat the car's value on the day.

Both markers are logged by the insurer and stay attached to the vehicle identification number permanently. They do not wash off after a good repair, an MOT pass, or three changes of keeper. And here is the bit that catches people out: the V5C does not shout about it. The logbook looks normal. The marker lives in the history check, which means the person who finds out is often the person you sold it to.

There is no VIC check any more either - that scheme was wound up back in 2015 - so nobody official is inspecting the quality of the structural repair. That job falls to you, and it is the single biggest line item the discount has to cover.

The photo folder is a story, not evidence

A dozen camera-phone shots of a bent front end and then a straight one tell you almost nothing. They show what somebody chose to photograph on the days they chose to photograph it.

What they cannot show you:

• Whether the shell was pulled on a jig and measured, or pulled with a ratchet strap and hope
• Whether damaged sections were cut and replaced properly, or filled and painted over
• Whether the airbags were replaced with matching units or the warning light was dealt with by other means
• Whether suspension and steering geometry came back into tolerance after the hit
• Whether cavity wax and seam sealer went back on, or the repair will be quietly rusting from the inside out in three winters
• Whether the paint match will hold up under a forecourt light in June

If the repair is genuinely good, the person who did it will usually have the invoice, the geometry printout and the parts receipts. If all you get is a photo album and a shrug, you are being asked to underwrite the work yourself.

The three costs that eat the discount

Repair risk. Even if the car is straight today, some Cat S repairs have a tail. Tyre wear you cannot explain, a boot that never quite shuts the same, a steering wheel slightly off centre on a motorway. Those come back as warranty claims and unpaid-labour time, not invoices.

The resale hit. This never goes away. A Cat S typically wants to be bought at a meaningful chunk under clean book, and it wants to be sold at a chunk under clean retail too. That second discount is not a one-off - it is baked into every future sale of that car for the rest of its life. You are not buying a cheap car, you are buying a car that will always be cheap.

Friction. Some insurers will not touch a Cat S, or will only offer third-party cover, or will want an engineer's report. Some lenders will not advance money against one. Some buyers will walk the moment the history check lands on the desk, and a fair few part-exchange valuations will come back noticeably lighter. Every one of those is a real cost even though none of them appear on the invoice.

Doing the sums on a real example

Say a clean example of the car retails at £10,000 and the Cat S is being offered to you at £6,200. That £3,800 gap feels enormous. Now start spending it.

• Repairs and paint you can see: say £1,400
• Putting right what the last repair missed: budget something, even if it is only £400
• The discount you will have to give the next buyer: realistically £1,500 to £2,000 off clean retail, because nobody pays clean money for a marked car
• Extra days on the forecourt while buyers with finance and nervous partners filter themselves out: two months of holding cost
• The odd deal that dies at the history-check stage: price that in as a percentage

Run that and the £3,800 gap is mostly gone. It can still work - but only if the repair is genuinely sound and you have been honest with yourself about the resale number rather than using the clean book price as your target.

The exit plan is the whole game

Before you buy, answer one question: who is my buyer at the end of this, and what will they pay?

If the answer is a trader who buys anything at the right number, fine - but that is a wholesale exit, not a retail one, and it needs pricing accordingly. If the answer is a private buyer who will not check, that is not an exit plan, it is a complaint waiting to happen and a reputation you cannot get back.

If the answer is "an enthusiast who wants this exact car, knows what Cat S means, and will pay a sensible price for a well-documented repair", you are in business. That buyer exists, but they want paperwork, photographs of the damage before repair, and the invoice from whoever did the work.

Calculated bet, or trapped purchase?

The tell is usually paperwork and time. A calculated bet looks like this: full damage photos including the before, a repair invoice from a named bodyshop, geometry printout, parts receipts for airbags and sensors if they were replaced, a price that leaves genuine margin after the resale discount is applied, and a plan for who buys it and when.

A trapped purchase looks like: a photo folder with gaps, a repair done quickly and quietly, a seller who gets defensive when you mention a jig, a price that only works if you sell it to someone who does not check, and a car sitting on your forecourt for four months while you slowly talk yourself into dropping the price.

None of this is a reason to avoid Cat S cars. It is a reason to stop treating the discount as free money. The marker is permanent, the risk is real, and the only thing that ever pays for it is a number you agreed to at the start.

Price it properly and a Cat S can be one of the better deals on the lot. Price it on vibes and a tidy-looking bonnet, and you have just bought somebody else's problem at retail.