When you go to the home improvement store, find out how much 12 gallons of the paint you want would cost, and that will help you determine your cost. Maybe it's a low-quality paint that costs $30, in which case you're looking at about $360 for paint. If you choose high-quality paint that costs around $70, your total paint cost could be closer to $840. Professionals also recommend that you add an extra 10 or 20 percent to your total square footage, depending on the type of siding you have. Some textures require extra paint because they're rough. This is especially true with wood and stucco siding.
To win work, contractors generally have to bid against other suppliers. To make an accurate bid, they estimate the time and materials required to complete the job. They measure the area to be painted and discuss the type of finish the customer requires. They assess the quality of the surfaces to work out how much remedial work they must carry out before painting. They might have to remove old paint or wall coverings, or repair cracks and other damage. They also calculate the cost of any essential equipment, such as scaffolding for exterior walls.