I actually installed one several years ago. Same type of installation. A small powder room. Teak and holly floor. Looked sharp. The original sink I installed was designed for just a cold water supply. The owner wanted the tap water to be warmer, so I added a thermostatic valve before it (accessible, in a compartment below the sink). I had hot and cold supply lines feeding the TS mixing valve, then there was a single run of tubing from the TS valve to the sink's tap. So the water temperature was non-selectable from the folding sink itself, but it could be tweaked by the owner if needed by accessing the tempering valve in the compartment. The temp is basically a "set and forget" type of thing. Have your guy look for an "in-line thermostatic valve", or sometimes referred to as an "in-line tempering valve", if you want to go that route. They're around $60-$75. The drain as well is quite simple. Standard. To operate, you unfold the sink. Turn on the water to wash. To empty the bowl you fold it up. Water pours out the back of the bowl into the sink's housing and is funneled down the drain. Some bowls have a deformation on the back rim of the bowl, sort of like a pouring lip on a tea pot. Probably a bad description. But the idea is that if the bowl overflows, water will outflow over the back of the rim through that spout and go down the drain. The sink I installed did not have that feature. To comply with the overflow, I had to modify the bowl on the sink. I drilled a hole about 3/8" diameter in the top back of the bowl, about a 3/4" or so below the rim. Then I added a small piece of metal tubing, 1/2" diameter and about 3/4" long, right behind the hole. The piece of tubing acted as a chute to direct water that went through the overflow hole down the drain. Without that piece of tubing, overflow water would have simply run down the outside of the bowl and cascaded off the bottom of the bowl and on to the floor. You'll need to add a trap. That's about it. The sink I installed was designed for the plumbing to be hidden. I hid the trap and the supply shut off valve (and the TS tempering valve) in a wall stud bay compartment behind a hidden door built in to the wall's wainscot. If you want exposed plumbing you can do that, but be careful how it projects from the wall in relation to the sink. You can get metal tubing in myriad finishes, from rough and rustic to fine polished metal. This post was edited by mongoct on Mon, Oct 28, 13 at 11:40

Thank you all for your feedback...it's getting closer to reality. Plumber was here this week so I believe we have resolution on the sink plumbing and cabinet. Lucy132, we are still working on that. As of now, no resolution! One option for us would be the wall that the door is on (by the sink). We have to resolve hand towels too. If we could have moved the door, we would and that would have helped but no such luck :( we did move the cabinet on the wall over the toilet so there is opportunity there but you'd still have to stage your towel by the sink or track water over floor. There are shower door options with towel bars but we opted against that.

constant humidity and expansion and contraction, isn't the best thing for wood. nor is the moisture. so if you're going to bring wood in the bathroom, make sure you have extra exhaust fans/windows in order to keep the humidity at bay. You may just want to forgo it all together if people will be coming in from the pool. you'd basically be doing a 'rug' insert w/the tile. use your imagination on these.. this is a small example, in reverse. imagine if the black tile was your wood,,,,you'd tile your 'rug' the length of where you want it. consider using some pebble tile or something like these cement tiles.

There is an organization called Little People of America. You should contact them. In addition there have been several tv shows featuring little people, my favorite being The Little Couple. From watching these shows, I noticed the stature and the needs vary widely depending on each person’s medical needs and actual height. I think you should look there to begin your journey. Of course, there will probably be some on a Houzz with this experience.