My first ideas include a woodstove, 2 mattresses 70 x 200 cm. The mattresses can be tilted so they are both vertical for maximum room, or a sofa, or two bunk beds above each other. It should also be possible to remove the upper bed and place it besides the lower, so a mattress 140 x 200 arises.
On the doorside i would like a shallow closet, with foldable cooker and sink.
Then theres the idea of a expandable shower/toilet by a hidden and retractable separation wall.
See if it fits.
