Whether you're painting a hallway, bedroom or the interior of your entire house, maybe even a storage cabinet in your laundry room, everything you do from the very beginning on through to the last brush stroke will be reflected in the amount of quality time you invest in your initial prep work. Thorough cleaning and attention to detail are essential for whatever it is you're getting ready to paint. Even brand new plaster needs sealing. Cracks and holes must be filled, and surfaces must be clean, smooth and dry. The work in the preparation along with the right paint used for the required job, the longer lasting the finish.