My feeling's about how small you can go to fit in a mono slip rubs right up against the inevitability of slip availability become more of a scarce commodity in the sailing destination regions. Scarce as well as costly. So, if you're lucky to find one that sheltered pier that only a shallow draft boat can ford and with shorepower, access to water, supplies, that would be ideal.
If all you had was a mooring buoy and open anchorage, then for me a condo proa with extended stay food and water capacity and creature comforts beckons.
A folding proa more befits a lean accommodations. A folding condo pro would be that fabled unicorn. Still, folding proas like the EX40 Air are very sensible, indeed.
Bob