William M wrote:

Bought an old Percival Sea Prince (twin engine with approximately
2,000 pounds useful with full fuel.

http://www.oldprops.f9.co.uk/Perciva...hotographs.htm

This might turn into an academic exercise only, but would really like
to save on car rental, hotel and restaurant costs when traveling. I've
already figured out the transportation portion with a scooter and side
car, but need thoughts on cabin heating, stove, fridge, shower, sink,
toilet, etc.

A "Homelite" portable generator for 120/220 power. A/C electric heating
would be the safest. Maybe even permanently mounted in the tail (or
nose) like an APU on the big birds or run outside and away from the
plane for noise reduction, simplicity and safety.

A slide out cooking surface, like what is used for tailgating, would be
the safest. A tarp/canopy could provide additional shade or protection
from the weather, though you do have a large wing for that too. There
are several multipower refrigerators available. It could have power from
the main or a "house" battery, as well as from the generator or even
propane. The stove could be electric, propane or fueled by gas sumped
from the engines. What is the buss voltage of the aircraft? You'll
probably need a regulator to give a more standard 12v source for
appliances or to power an inverter (inflight microwave).

A bath module from a travel camper would be the most convenient, as it
provides the toilet, sink and shower in one unit. If the water tank were
overhead, gravity could provide pressure and if its over the holding
tank, that would capture the waste water. Grey water could be discharged
externally if permitted. A portapotty would be the easiest to install.