Jeff is probably correct in that there are probably few builders that can build such a creature.
THEN, speaking as a contractor, no not a boat builder, when "I" get clients that I realize are contacting numerous folks for bids, reality is, I bid higher as the potential client will probably be a PITA, along with needing to CMA on potential cost issues that may come up that some clients I can explain the "I can build this potential problem in, or set it off as a potential, if it occurs, it will cost X if not, then I do not charge you, or leave it out, and I end up eating it" So depending upon the initial contact how you want things bid, will depend upon the how interested I am in bidding the project.
Then again, I could see how for this project, one might have to contact MANY builders to figure out who can, is willing etc to except such a job too!
She drives me boat,
I drives me dinghy!