how much should i charge for painting a ceiling
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.igure it out like a professional contractor would. Ask the painter how long it is going to take them in number of hours. Muliply this by $25.00 - $40.00 / HR depending on the detail and type of finish (likely around $30.00). Add it to the costs and add in 25-35% for overhead if you are dealing with a legit business.