One of the most desirable properties in Tokyo is Chateau Mita, located in Minato Ward within walking distance of several embassies and Tokyo Tower and less than 10 minutes from four subway stations. The apartment building was constructed in 1964 and by 2000 there were persistent problems with plumbing and wiring, so the resident-owners decided to rebuild the eight-story structure in 2010.

Because of the choice location, two major real estate developers became involved and when work was finished last year, the building, now dubbed The Residence Mita, had added 16 stories and 175 units. Those units were sold to offset the renovation cost for existing residents, not to mention make money for the developers. They sold out immediately at an average price of more than ¥100 million, and the highest at ¥270 million.

Two blocks away is another residential building, the Toyo Mita Itchome Apartments, which contains about the same number of units as Chateau Mita originally did and was built in 1991. Location-wise, it's better than Chateau Mita, only a minute from Akabanebashi Station. But the units are rentals, and residents on average pay ¥50,000 a month. How is that possible for housing situated on some of the most expensive real estate in the world?