Just wanted a little advice on my guest house plans. My current setup is I have a separate garage that is two stories. The bottom floor is the garage that has in-floor radiant heating and keeps the garage at about 35 degrees in the winter. I do not have water or sewage to the building so I am going to use a composting toilet and I plan to put a water tank in the garage (about 350-500 gallon) to store water to pump upstairs to use throughout the guest house. It will not have washer/dryer, no toilet obviously, and no dishwasher. So the water will only be for showers and doing dishes. I plan to keep the tank topped off with water from outside tap (we have a well) in summer and it will see very little use in the winter if any. I will plumb grey water into another tank into the garage to use on garden and if I have a lot I will just empty grey water into our septic tank that the house uses. My question or hope for some advice, is what type of set-up do you all recommend to pump water upstairs to the house to keep water pressure at 20-30 (standard water pressure in a house) for the kitchen sink, hot water heater, bathroom sink, and shower? What size of tank do you think I will need? I calculated that guests would use about 30 gallons a day. I am thinking a 350 gallon plastic tank would work. Then a pump that is pressure regulated to keep pressure in water lines. What type of pump do you think I would need? Would I need a pressure tank?