If you can not find what you are looking for in the 65 feet to 85 feet range, or the catamaran you are looking for is larger then 90 feet to begin with, most likely your option is limited to full interior architect Custom.
In this case your first step is to find a marine architect/design group, or an all inclusive yard that are experienced, financially sound and fully capable of realizing your mega catamaran dream.
Just to highlight a few: VPLP, Marc Lombard, Blubay, Berret-Racoupeau, or Gilles Ollier Design Team would be a good place to start shopping.
Selection of the marine architect, or design team
Here are some key points that you will have to define before you start looking.
Your overall budget for the boat
A length that you would like to build
Performance VS. Comfort
Time of delivery
With this information you can start your search.
Based on this information you may select more then one designer. At this point it is absolutely necessary to have a face to face meeting, for you to be able to make the final selection.
Pre-Project Plan
The scope of the pre project plan is to define more precise drawing of the catamaran, more defined interior and exterior layout, big item equipment list. The creation of this document will be the work of the designer as much as the buyer’s feedback as the project is taking shape.
At the end you will have a comprehensive document that outlines the project.
This could take a month, maybe two depending on the size of the boat, and on if the designer had some plans already ahead. The charge for the Pre Project Plan can vary according to the size of the boat, $10.000-40.000
If you are pleased with the plans then we enter the Defined Project phase.
Define Project Plan
The pre project plan here gets expanded into an extensive in depth document, which then can be offered to selected yards for a bid on the project. During this phase the designers work closely with subcontractors (interior designer) to come up with the sail plan, interior, systems engineering, 3D design, technical drawings, and so on. This document may add up to be 400 plus pages, and can detail items like the type of speaker wire that will go on board.
During this time there is constant communication between buyer, buyer’s project manager, and the yard.
The definitive project plan can take as much as 4-6 months, depending on the size of the boat. It is hard to put a price on the cost, but it is fair to say the cost of pre project plan + defined project plan+ project consulting throughout construction = about 5% of the overall cost of the boat.
Yard, Building Project
The defined project plan then will be sent to selected group of yards, for a quote on the project. The selection of these yards is done by looking at yards that have been recommended by the designers, project manager, or the buyer.
Choosing the actual yard will be done by the buyer (hopefully with input from project manager and designer). This is the most important and can be the most difficult step.
Not only do we have to find a yard with a competitive price but the yard needs to have the proper financial standing, prior experience (referrals), and the available schedule to fit your Catamaran project in a timely fashion that suits you. Geographical location will play a role as well. Is the country’s economy and government stable? Friendly? Currency VS. US $?
Can they give proper guaranty to make you feel that your money is safe? I feel that these points need to be made not to discourage you, but to raise awareness. We are there to help at each step, so will be the design group. It is our best interest that at the end you sail away with your dream mega catamaran.