how much cost paint house
1 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.
1 Interior paint itself costs anywhere from $12-$50 or more a gallon, depending on the quality. 2  Painting a 12x12-foot room, both walls and ceiling, can require $25-$100 worth of paint, plus $10-$50 for primer, brushes, rollers, drop clothes and other supplies.