As an experienced interior painting company in Williamsburg, Virginia we have painted the interior of thousands of homes. With hundreds of five star reviews we know how much a quality interior painting project should cost. This article is to help guide you in making the right decision when hiring an interior painting contractor. When completing interior painting in Williamsburg, Virginia we recommend doing the entire house at the same time. This is easily the fastest way to save you $$$. When it comes to interior painting the number one question, we get asked is how much does a whole house interior painting project cost. The short answer is it varies, but on average it costs between $3-$6 per sq ft. A few factors include the full scope of work: Ceilings/walls/trim or walls/trim or just walls.