Take a look at the “Sky” in Monaco. This penthouse -once completed- is supposed to be the most expensive apartment in the world. It is expected to cost 400 million US dollars. It is located at 170m above ground and the 3.300 square meter apartment is separated in 5 floors. Its view to the coastline is breathtaking, while its high ceiling and huge patio are impressive as well.

Luckily for its developers, almost 30% of Monaco residents are millionaires, so finding a buyer will not be much of a problem.