There are 2 neighborhoods in Japan that cater to the super-rich. One is Den-En-Chofu in Tokyo, and another is Roku-Roku-Sou in Ashiya.
While Den-En-Chofu recently lifted minimum area requirements to ease development, Roku-Roku-Sou maintains the highest standards and exclusivity, home to sports stars, bankers, and directors of TOPIX-listed corporations.
We are glad to introduce to the market a 535m2 plot of virgin land with breathtaking views of Osaka Bay
Lot coverage ratio is 30%, Floor area ratio is 80% so it is possible to build a house of up to 400m2 of floor area.
Here is an idea of how to develop the plot: https://dodici12.com/works/hyogoken-glass-house/
More information is available upon request.