9. $4 billion Palace of the People in Bucharest, Romania
The most costly administrative building in the world is located in Bucharest and is also referred to as the Palace of the Parliament. Each year, the cost of electricity, heating, and lighting exceeds $6 million.
The People’s Palace was built on a project ordered by dictator Nicolae Ceaușescu of Romania and finished in 1997. It is 70% unoccupied and has a floor space of more than 3.9 million square feet.