Are you asking what it would cost you or what a builder pays to build a house in a new subdivision? The costs for building a single custom house are higher for a homeowner trying to build a custom house then a builder building a bunch of houses at the same time, same location. Are you talking about building in the Coastal Zone and thus need to pay for a coastal zone permit? Are you including costs of architect or do you have plans? Are you assuming current high lumber prices and steel prices will have fallen back down to normal before building?