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.
Climate is another factor to consider. Sunlight, wind, rain and salty weather can all wear out exterior paint. Oil-based paint is durable against wind, rain and temperature changes, but sunlight tends to degrade it. Alkyd paint chalks and sheds very thin layers when it begins to wear. Latex paint is the more durable option for very sun-drenched and relatively dry climate areas. Latex paint with high vinyl content should be avoided, however. Acrylic resin is by far the more durable binder for outdoor latex paint.
Thanks, all, for your time & efforts adding to the article & comments, especially Dave urging requesting both General Liability AND Worker Compensation insurance certificates to protect from real & fraudulent liability--from my experience especially in California, where insurance fraud is a popular income thief, even causing car collisions to collect.
The pros were split on this tip. "Masking tape is problematic," says Mark Dixon, a painter in Missoula, Montana, and author of "House Painting Inside and Out" (Taunton Press, 1997). "Paint can bleed behind the tape, or remove the paint it's stuck to." Another problem is bridging. "Latex paints form a skin," says Dixon. "Removing painted tape can tear the skin, resulting in a ragged rather than a sharp line." Lastly, taping takes time. "Learning how to cut in with a brush takes practice, but if you can do it, you'll leave most tapers in the dust," Dixon says. (Cutting in is painting just the surface you want, not the surface adjacent to it — for example, where a wall meets the ceiling.) On the other hand, "If you can't cut in, you can't beat tape," says Span. The pros we spoke with all recommend painter's (blue) tape because it's easier to remove than masking tape. To prevent bleeding, Span uses a putty knife to bed the tape. After letting the paint dry, he scores the edge of the tape line with a utility knife to avoid tearing the paint.
Thorough preparation is essential to ensure a good finish. Contractors might have to fill cracks or holes and remove old paint if it is badly worn, peeling or flaking. They remove all paint and apply a suitable primer to the bare surface. If the existing paint is in reasonable condition, they clean it and rub it with abrasive material to provide a key for the new paint. On new surfaces, such as bare wood or fresh plaster, they apply a suitable seal, followed by a primer coat.
The article and comments were great information to have before deciding how to go about getting a painting job done. I think the important point is that there are several key choices (who to do the work; color, sheen, quality, of paint; how many coats; amount of prep/repairs to be done and by whom, how long the job will take, provisions for changes, how detailed the contract needs to be; advanced deposit/progress payments/final payment; final inspection, etc.) that need to be made and it requires advanced research and planning in order to become well enough informed to make the right choices. Then it requires spending sufficient time to check materials and inspect the quality of the work while it is on-going, raher than waiting to do it all at the end. President Reagan's philosophy of "Trust, but verify." applies.
Buying a can of premium paint, then bait and switch over to low-line products? Again, complete nonsense. Think about it for a moment; the Painter needs 5 gallons of wall finish. So, he buys one can of premium and the rest 'cheap'? How is he going to hide the 4 other gallons? What's he going to hide it in??? He only has ONE gallon of premium. It's not as though he's going to keep older can labels, they would be covered in paint of a different colour.

Colorado Painting Company