From Builder Magazine and the U.S. Census Bureau on July 11, 2019:
The U.S. Census Bureau recently released the 2018 Characteristics of New Housing Report, which shows that the median size of a completed single-family house was 2,386 square feet. The median size of multifamily units built for rent was 1,081 square feet, while the median of those built for sale was 1,414 square feet. The median sales price of new single-family homes sold in 2018 was $326,400, while the average sales price was $385,000. The median size of a new single-family home sold in 2018 was 2,435 square feet. Finally, 119,000 contractor-built single-family homes were started in 2018. The median contract price was $281,200.