Prefab houses typically cost $30 to $100 per square foot without land, finishing, site work, or alterations. Prefabricated houses are less expensive than kit homes or shipping container homes. The price of a prefab house depends on the size, location, and construction quality. The total cost of a prefab house is based on several factors, such as size, location, amenities included, etc. The average cost of a prefab house is around $60 to $80 per square foot. Size is one of the major factors that influence the overall cost of a prefab house. Large families may need multiple units to accommodate all their needs, which increases the cost per square foot. Other factors include location (if you want energy efficiency for example it makes more sense to build off-grid), builder's quality, options selected by owner, etc. There are many ways to save money when building a home - including using a prefab house as your starting point. In fact, there are many examples of cheap prefab houses out there - so check out some of our favorite ideas below! Square footage is another term for floor space. A room is considered square if it has an area of 100 square feet.