start day 19/8, return day 22/8
any flight will be fine, cheapest possible
doesn't matter staying in what hotel or inn, cheapest possible
not a must to buy things
1. go to tokyo or you may suggest
2. hot spring hotel staying 1 night
3. fresh fish market to eat 壽司 and 魚生
4. 1 day to visit some famous places
5. enjoy some other special japanese food as well
I just got around 6000 budjet, i know it's not easy to do it.