Rich neighbourhoods in Tokyo

Tokyo is a huge metropolis. Most people live in apartments or small houses. But where do the super rich live ? What's Tokyo's equivalent of Beverly Hills or Upper East Side, where celebrities or big company owners have their villas ?

According to a ranking I found on a Japanese site, the up cust resides in these neighbourhoods :

Setagaya Ward

- Shōtō
- Seijō
- Tsurumaki

Ōta Ward

- Denenchōfu
- Todoroki

Meguro Ward

- Aobadai

Minato Ward

- Shirokanedai
- Higashi Gotanda
- Minami Aoyama
- Minami Azabu

Bunkyō Ward

- Kohinata


Many rich Tokyoites have a second residence in the mountain resort of Karuizawa.

The municipality with the highest average income in Japan is Ashiya (芦屋) between Kobe and Osaka.

I wonder what Japanese villas look like. Is there any Californian style villas with swimming pool and tennis court in those rich neighbourhoods ? Anything fancy looking like European castles ?