You’re right, unfortunately that’s not how insurance companies work.
I’ve had so many conversations over the years with different companies about the prices to actually replace our cars’ should the worst happen.
I’ve had other cars insured with specialist companies who offer an agreed valuation.
Got one for our mk1 mx5, my mate has one on his focus RS, 04 reg same year and mileage as my Cupra R but unfortunately our car’s don’t fit their criteria!? That’s what I’ve been told every year. ( as desirable as a Ford apparently)
Last year however I spoke to someone who said next year as it would be over 20 years old he would speak to the underwriter and see if it would be accepted on a classic/ Specilist policy which would include an agreed valuation.
it’s an additional cost of £20 for the first year, and would have to be backed up with photos of the car and evidence of similar cars on the market.
I have been saving adverts for a few years now with Mk1 ‘R’s for sale as evidence. Lol
So if I get anywhere this time I will report back on here.