The living quarters: Now that is a bit misleading as it is actually a dressing room, with a loft in the nose. I went to a thrift store and purchased an old chest of drawers, a square bedside table, and a small bench seat. I painted all of them black as I figured that would show dirt less than white, but I failed to consider the white horse hair. Those pieces cost me a bit over a hundred dollars and the paint. I already had an upright wooden cabinet on the back porch so it joined the paint session. The four pieces were then screwed down to the wooden trailer floor to give them stability. I bought a piece of fabric and covered the bench, a spread from a dollar store, and used the flannel sheets I already had. Won the horse at a CMO, painted it and hung it from a twig wreath. Total cost well under $200. Not a conversion by any means. But I have a hoof boot drawer, a spare tack drawer, a drawer for my body glide, monkey butt, and small flash lights. The cabinet houses the entire "kitchen & bath" A dish pan, plastic cutlery, paper towels, first aid kit, soap, towels, and washcloth. The small bedside table holds my socks, riding tights etc. The rack that was already in the trailer holds saddles, pads, and blankets. The bridle rack in the trailer holds those, and lead ropes, halters, and one hook I hang rain gear from.
The curtains I pull to hide the back of the trailer or to use for privacy when changing clothes. The divider from front to back opens into the horse trailer where I sweep up the shavings into one corner, and set up a port-a-pot for use at night. An area also gets cleaned to sit the zippered up hay bale bag with access to it from the door in the back.
In the summer, if I go somewhere that I can pay for electric, I carry a grounded extension cord and a box fan. If it is hot at least I can keep the breeze moving, and by nightfall it moves enough air to make for comfortable sleep (if only I could) and filters out all the background noise in camp which is helpful as well.
When the weather is cold I use a buddy heater that runs off a small propane tank. I have very mixed feelings about it. My trailer has slats in the back so there is plenty of air circulating to keep me from gassing myself with carbon monoxide, but I continue to have mild feelings of paranoia about the thing and wish there was a better way! However, it has kept me from freezing to death, but requires that I get up and change the tank in the middle of the night as it is only good for about four hours total.
For water I carry a case of drinking water with squirt bottle lids for myself, and use them for quick and easy hand washing. A bucket of clean water from home takes care of the rest. Horse water is in a large tank in the bed of the truck.