mental exercise - vardo

i want to make a vardo
a gypsyish wagon
money, time, ability - all current constraints
and it doesn't need to look gypsyish
just the concept

thoughts so far:

how big?
i measured my SUV. it's about 5+ x 14 feet.
ok, i could feasibly tow 6 or 7 x 14 feet [external dimensions]
internal dimensions i figure knock about a foot off that for insulation and structure
there are available options for tandem axle heavy duty equipment trailers in those dimensions
looks like 10 feet tall [above the trailer] would work: would give me 3 feet of sleeping loft, 8 inches of under floor insulation and storage and about 6 feet


what goes in it?
bedroom, bathroom, kitchen, and 'awake' living space
i lie down to sleep so i would follow the traditional pattern for tiny houses: a sleeping loft

i would skip the porch - if i'm parked, i can just go outside. if i'm on the move, i can't use the porch anyway

getting ideas together for ways to make things fit into it.

some of the extreme space saving thoughts include:

pullman style folding sink in the bathroom
or possibly a sink-positive
http://www.sinkpositive.com/

either a folding sink, a hughie sink or a yacht galley sink with a fold down faucet in the kitchen

remember what i said about under floor storage? i found an idea from a japanese product site for under floor sliding storage bins. you have one access hatch and bins that you can slide back and forth to overlap the hatch to access the contents.
http://www.monotsukuri.net/japan/yukasita/yukasita.htm
theirs are a little deeper than i would plan [they even have one you can climb halfway into for a semi basement!] but i don't see any reason existing sliding track drawer products couldn't be converted to work the same way at about a 6 inch depth in the center of the floor and still allow for things like water/sewer tanks, electrical and insulation around the edges.

also in the extreme space saving category is a concept i dreamed about [here's the white hot hammer for this week] : a tambour styled pantry.
tambour being the rolling part of a roll top desk or the door that curves back into the wall
more on that when i have developed the idea more, but the vision includes a curved ceiling track and some sort of hanging, connected narrow/shallow shelves that roll back into a deep but narrow wall pocket.

of course the usual folding tables and fold out computer shelving is in order, all apparently available from ikea.

energy efficiency is also a major goal.
being obviously off grid, as any mobile structure must be, i will need power generation and storage.
AGM deep cycle batteries are an option for storage
all that lovely roof can be solar [i'm liking the brunton solar roll for right now, but more efficient options are coming every day]
and of course any moving thing can benefit from the power harnessed by mini windmills. i'd love to come up with some vertical mini turbines that collect any time i take it down the road.

things still to work out:

i want a tub, i want a shower. can i find or build a sitting up style japanese soaking tub with a walk in door that will fit?
the smallest footprint i can find for a walk in tub is 36x34. with a 5 foot interior width, 34 inches takes up most of the room available at one end.
not sure what the tiniest toilet i can find will be - i did see some tiny ones in europe
but i recommend NOT doing a google search for 'tiny toilet' with your safe search filters off. ewwwww

it's bedtime now, more another day