I agree with Lance. If you are building a home on an empty lot there are many costs involved: Perk tests, bringing streets/driveway access to the home to be built, utilities such as water or electricity, sewer, etc. Some lots have those in place already. Then the plans and permits and design reviews may take some time and of course money. The actual cost to build is usually about $300-400 per square foot as far as what i've heard for just construction of a building on a lot or a room addition or expanding an existing house. It depends if the builder is also local or from out of state and if he has a crew or is a one-man operation. Back in l986 i remember hearing that it was $100 per sq ft. Since then there are new codes and more stringent building requirements which make the cost of building higher.