Not sure what the cost of the wood was exactly, as I never asked for a breakdown, but I reckon it worked out somewhere around £85 a square metre (which would fit in roughly with the cheapest I could find it online) - unfortunately walnut is a lot more expensive than oak, but it was what we had our hearts set on because of the colours and grain structure.
The underlay was some sort of white foam stuff with a silver thermal layer on the bottom - sorry, I didn't get too excited about it! ;)

