Residential construction is the business of building and selling individual and multi-family dewellings. The market fragments into single-unit, manufactured, duplex, quad-plex, and apartments and condominiums. Manufactured housing further divides into mobile homes and pre-built houses. The business varies primarily in the size and scale of the operations. In the simplist form, a builder buys a peice of land, develops the land by clearing and grading it, and constructing roads, sidewalks, drainage, waste removal, electrical and water supplies and etc..