Ireaney:
(I changed my avatar after i saw your dogs, itīs my cat) 
Itīs not easy to find the right catamaran. So many different models and should i buy new or used, build a kit or....
I donīt think the idea to build a
Fusion 40 in europe will be cost effective, maybe poland or estonia, or lattvia. Or by yourself at a cheap place. I think materialcosts will be a big problem in this part of europe.
Spirited 380 and
Pacific cat 40 is nice cats but will probably get more expencive than a used Privilege 435 as you said. The
Oram 44C is probably the cheapest to build.
I have changed my list on interesting catamarans 20 times right now. We would like to have the catamaran as a extra house the short swedish summertime. And sail to warmer wintertime...
I had plans for La Rochelle....but right now we have to much to do at work...But i will try.
The pic is from my house jan 2007.