The last time I was there kenko hoken was about 4000yen per month for 3 people
travel insurance is about $500au for 1person for 3 months
plus if we catch a cold or something minor
it's much easier to go to the local hospital with kenko hoken
then paying a large amount of money and claiming later
I'm not sure about the taxes some don't start until you have been there a year
we didn't pay nenkin when we we're there 5 years ago
I think school is compulsory and they give you a harder time if you don't attend
thanks for your replys so far