This isn't going to work as the claims guy is saying I'll only get the current value??? I'm finding it difficult to plaster into his brain that my car's market value is worth more than he tried to pull one on me over. 4500 to 5k rubbish so he went online and I showed him a 6500k one but he's being funny about that?.
It's not the claims guy who decides what the insurance will pay out though. He can give his opinion on where the market is. You can prove where it really is, with actual examples of the market. They have an obligation to put you back to where you were, and if that costs £6k rather than £4.5k, it's on them to prove otherwise. And at the end of the day, you don't "have" to settle on whatever they offer you.
I've done it before. Been offered £3k on a written off car, prove the market value for replacement was £5k, get original offer upped substantially. Sure, you might not get the full £6500, but you should get very close to it if you push it hard enough. Just remember, you are not dealing with YOUR insurance company here, who CAN play hardball. It is the third party insurance people, and they are meant to be pleasing YOU as it isn't your policy being claimed on.