I am going to Tokyo in 2 months. Will be exchanging some currency. I should not worry if I get some 2000 then from the conversation, right? Is cash the dominant payment in Japan? If so how much does one need for a 3 day stay excluding hotels as that will be known in advance. Just an understanding of cost there. I know it all depends on one lifestyle but its my first time and I would like to see the city in a typical touristy way.