I think that a 12ft version of Jon Montgomery's Catapult would be very suitable. It would be quite narrow with the hulls deflated, but not taken off the beams. A quick pump, mast up, sails on and away you go <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />
This is quite a fast design - I used to beat Condors and Hobie 16s to the windward mark, racing a standard 5m Catapult. http://www.catapultcats.com