One inlet can serve an area of about 700-800 square feet. In an existing home, the inlet valve should be placed near an electrical outlet to provide electricity to the Beam power brush. Electrified inlet valves are available for new construction. For more power, the fewer the inlets used the better. And be sure the hose will reach from the inlet valve to all corners (and around furniture) in the rooms you want to vacuum. Do not install inlet valves in a wall where there is a pocket door or behind a door. If you prefer, inlets can be installed in the floor.