The risks the photos do not show.

Some failures are so common on an engine or platform that the make and year tell you half the story. Each lot is checked against a defect database, for example:

• BMW N47 timing chain, 2008 to 2012.
• VW DQ200 and DQ250 DSG mechatronic failures.
• Audi 2.0 TFSI oil consumption before 2013.
• Range Rover air suspension compressor and bags.

When the damage class lines up with a known fault, say engine damage on a 2010 BMW 320d, the analysis says so: that may not be what crashed the car, it may be why the car is at auction.

Every risk is tagged low, medium or high and listed with the high ones on top. A high flag is a reason to walk away or to price the lot as a gamble. A low flag is a line to keep in mind at preview day.

• Flood history. Always worth less to the next buyer, however clean the repair.
• Branded title. What the paperwork looks like for each category.
• Missing V5. What it costs and how long it takes to recover the logbook.
• Stolen and recovered. What that means for the paperwork and the insurer’s payout.

An explicit list on every analysis, covering risk that exists but cannot be priced from the listing:

• Engine compression.
• Gearbox internals and clutch pack wear.
• ECU fault codes.
• Air conditioning condenser leaks.
• Frame rot under the panels.

It sets your expectations: a confident damage read still cannot say whether the engine has compression.

An insurer wrote this car off. If the visible damage looks like a £600 bumper on a £4,000 car, something else is going on, and CarMargin flags the gap between what you can see and what the category implies.