Thanks for the link, Danny...that explains it!
For water, the decision I've cast in Jell-o is to have a small sink in the counter next to the bathroom. I will have a handpump connected to a small on board water tank for dry camping. I will also have provisions for connecting to the water supply in a rv park with hookups. The bathroom will have shower capabilities only if connected to a water supply. I'm going to use the
Eccotemp L5 on-demand water heater for hot water. I'm going to mount it externally, and run a single supply of water to the shower and to the faucet for the sink. I'll adjust the unit to always deliver a good warm temp. Grey water will either be with a tank under the unit or preferably to the sewer connection at the RV park.
The AC was a design decision I made early on that I regret. I had to frame it when building the walls so I determined the location early on. The vents blow up, so I figured it would be like a hotel AC, and I could access fresh air from the bottom of the camper for the air that blows through the condenser. After I build the cabinet, I figured out that I probably should have made it higher, but I think it will be okay. When I saw Steve's Puffin, there were many aspects I liked, but I thought "I would do this part a little differently". I will probably think the same of MY design when done.
The black thing is a Coleman thermoelectric refrigerator. Very light (17 lbs I think); runs on 12V, draws 4 amps. Only practical with a 12V storage battery to power it when stoppiing while in-transit (Stuckey's - Eat Here Get Gas). And I will need to have the tow vehicle wired to keep it charged while enroute. My jury is still out on that one too.
The design goal was the camper HAD to fit in the garage. I didn't want to pay a storage fee and the [insert adjective here] HOA won't let me keep it outside. So...the garage door is a little over 81 inches tall. I arrived at a height of 79 1/2" for the camper with a low profile vent on top of that. It fits. Inside, the drop floor is 9"deep, and the height from the dropped floor to the ceiling is 68". For my wife, it's a "standie". For me it's a "stoopie" (but just barely).