how much damage did mount fuji cause when it erupted?

Answer 1

http://www.asianresearch.org/articles/1605.html

In 1707, the large eruption known as Hoei hit the nation's capital, Edo. Volcanic ash blanketed the city, turning day into night, and many cities and farmland were damaged.

Answer 2

We don't know because it last erupted in 1708