If less than half the old paint is left, however, it may be worth stripping it all off. Guertin gets rid of stubborn remnants using shrouded grinders (like the PaintShaver), infrared paint strippers (such as the Speedheater), or chemical strippers (like Multi-Strip), then smooths the wood with a course or two of sanding. When siding (or bank accounts) can't take the shock of a total strip job, Rich O'Neil, of Masterwork Painting in Bedford, Massachusetts, has successfully hidden rough, well-adhered paint under Peel Bond, a thick primer.
For interior jobs, make sure you've cleaned all of the awkward spots, including behind the toilet, and picked up any knickknacks that might get in the way (e.g., soap containers, loofahs, and kitchen organizers). Removing the switch plates and outlet covers from the walls also goes a long way toward speeding up painting time—and painters' time is (your) money.
HIGHLY recommend this company. We needed to hire someone to paint the interior of our home. The owner came over initially to give a quote and was very nice. Talked to him about his family and his business. He is very experienced and takes pride in doing great work. They are licensed and have workers compensation insurance, which was really important for us. The actual painters included Sandy, who was amazing and helped me select the right paint colors for our house.