I moved out the minifridge and this is what's behind it. Those pipes go up into the showerhead, and the lower pipe runs across the bottom into the fresh water tank:
Here's a shot of the grey tank, starts at the toilet, then off to the sink:
Moving the grey tank hose and the water pipe around seems pretty straightforward, so my main concern is disrupting the shower setup. Since I didn't build any of this I can only guess the previous owner put the pump up at the showerhead, which is why the pipes stop off there before going to the sink. If that's the case, would this mean I'd need a second pump if I move the sink to across from the shower (above the fresh water tank)? Or could I just extend the hot/cold leads under the bus? seams like the latter solution would decrease water pressure to the sink.
Also, I'm starting to think he didn't hook up the water heater correctly, because why would there only be one pipe leading from the tank?
Granted we haven't had the chance to fill up the tank yet to test out the sink, it's possible only one side of the faucet works...