Sam Morris Yachts make "Semi Custom" boats. In the case of Sam Morris I guess it's "made". Pretty much they are made to the buyers preferred interior layout. The bulkheads are in place as is the engine space, water tanks, fuel tanks, holding tank etc. As an example, the interior layout in Brendon and a friends boat is totally different both in the pilot house and down below. His galley is in the same location but that where the similarities end below. The deck layout, the bow pulpit, push-pit and the rigs are the same with only minor changes which might be due to the year of manufacture. His is a year older. What that all means is that the interiors are finished on a one by one issue so there are no patterns to follow. I suppose that over time a builder will collect a stack of patterns and layouts for buyers to pick from and things can be mixed and matched but nothing like that of a production boat. You can't change that much in 38 or 40 feet so the interior design will have to be somewhat limited.