Cold molding is not the most common method anymore and 24 meters is very large! A commercial
is required right at about that size to operate.. so I hope you have that. A professional builder
who has experience in this method and size will most likely have a facility to build such a yacht. Look for professional boat yards in the area of concern and the builder
probably has designers they work
with... You may even want to hire some type of broker
who deals with new mega yacht builds, though I have no experience.
The fact that you ask "how much" is likely you can't afford this boat. The cost to build is highly dependent on how it is outfitted, but even for a very modest/minimal finished boat, I'd expect at least $2,000,000 USD and more like $4-5 million if you want it nicely appointed... even more for 'high-end'.
As for the design, I'm curious how you know the lamination schedule already, but do not have a designer
?.. Anyway, you can probably buy existing plans with some engineering support and spend under $200k, but if you want this designed from scratch, then at least double to triple that for design and engineering. I would expect 3 to 5 years from signing/paying for the design to having a completed custom 24m boat ready to sail.
Some rules of thumb $30 to $40 per pound of boat for the build cost. At 40 tonn, that would work
out to around $3 million.
Materials are typically 40-45% of total build cost.