My idea is to build downward, from a floating platform, so I create a spar-buoy structure, then put the living space on top, using the Basalt rebar (light-weight, flexible, comes in coils, thermo-plastic, so reshaping can be done) and geopolymer, using ferrocement techniques. First, build the floating wet/dry 'dock', build the stern section, with drive system, build the bow section/living quarters. Lower the stern through a central opening and start building and slip-casting downward, using seawater as ballast, until I reach the point of attaching the bow. My goal is a F.L.I.P.-like vessel, that can be a spar-buoy, and low-powered when vertical, then blow ballast and go horizontal, with power, for storm avoidance, if necessary.
It's one of the reasons I feel the need for a landing-craft, so I can bring supplies out, then go back and get the car, as a floating camper, while building. An Ephemerisle gathering would be a nice distraction, while I do the rest, but, ultimately, I plot the pieces that are liable to show me the most advantage, for the entire concept. I need a trailer to haul supplies to the nearest place to launch, then convert to landing craft, load, deliver and return for the car, or just camp on the landing craft, if parking is free.