Exterior paint averages $25-$40 a gallon, and a 3,000-square-foot home takes 15 or more gallons of paint, or $375-$600 just for the paint. However, really premium paint can cost $50-$100 a gallon, or $750-$1,500 for that large home. Doing it yourself also requires renting a pressure washer or sprayer for $50-$100 a day; extra-long ladders or scaffolding at $20-$75 daily; and a power sprayer for $50-$100 daily, plus masking tape, drop cloths and other supplies. However, it's possible to paint a large, two-story house for materials-only costs of $400-$600. Denver Home Painting
Wood is probably the most time-consuming when it comes to preparing it for paint. It has to be scraped and sanded until there isn’t a single chip or bit of loose paint in sight. Any wood siding or trim with wood rot will need to be replaced, and all cracks and holes need to be filled with epoxy filler. Brush painting and roll painting wood siding costs $43 per 100 sq. ft., and spray painting costs $34 per 100 sq. ft.
Prime. Dark colors, stains (once sealed), and previously unpainted surfaces (drywall, spackle, etc.) will need a primer coat, usually white. NOTE: most paint stores & home improvement centers will now tint primer (at no charge) to match fairly close to the color of the finished coat, that way two coats of primer need not be applied. Although not all surfaces need a prime coat, skip this step at your peril! Dark colors will likely show through the first -- or even the first couple-- topcoats of paint. Sealants and unpainted surfaces like spackle patches will absorb or repel moisture in a topcoat at a different level than the areas surrounding them. Applying a good primer coat will help even out these differences. Primer equalizes a wall to a uniform surface. It's like erasing a canvas before drawing a new picture. Although some will argue the point, you generally don't need to spend a great deal on primer or buy special primer. A cheap, 5 gallon (18.9 L) bucket of plain, flat white paint will usually do the trick and cover a large area. Give your primer at least 24 hours to dry (follow its instructions) before applying a topcoat.
For trim and doors, start with 1 gallon (3.8 L) of trim paint for every 600 sq feet of floor space. Purchase more at the store if/when needed. Trim is something that is difficult to calculate exactly, and it is more time-efficient to simply start with less than you need, and go buy more after you have used up the first round of paint and determined how much you will need to finish by seeing how much you have painted so far, compared to the gallons used. Denver House Painting