This work her is not more in progress but already finished. In an old White Dwarf edition I found an article about tabletop rules for boats, so I built three of them for my Minas Tirith warriors. Here are pictures from one of them, the others are very similar. As you can see, 8 models have enough space inside one boat.
The boat is made from thin cardboard. The shapes of the various parts are my own design, with some trial and error. I glued them together with paperstrips.
The parts are the bottom, the bow and the stern, 2 lower and 2 upper bulwarks, a steering rudder and 1 wooden stick glued between the sides to give more stability and to create a flat bottom (important!).
Here are the pictures: