Yes, last april its my second time go to japan. Still many suprise experience. Just decide the date and begin to book the accomodation by online. Choose free cancellation. Read review of hotel or hostel, recommend near JR station. train you can buy JR pass or any pass suitable for itinerary. If you travel around japan JR pass suitable. JR pass like Global pass in europe, but no need reservation like in europe except going to hokkaido you have to reserve your seat for free, cause there is non reserve car. Place of interest you can read from any blog, but for the first time you go to Tokyo, Kyoto and Osaka.

I am not sure, but there are 2 big malls: 100bangai forus you could look up their websites ... it will give you an idea maybe.

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