said by cdru:
The pressure tank and pump would only help for small uses of water. How much a small use would be is going to vary based on the pressure tank size. A shower for instance is likely to go through that capacity for modest sized tanks quickly and then you're right back to where you started.
The pressure and volume would be dependent on the capacity of the pump not the pressure tank. It would be no different than a well pump set up. The tank is just to keep the pump from cutting on every time water is drawn dropping the pressure If the pump is sized right you can pull all the water you want at the pressure you want.