I don't know how much all of your plans will cost but I just got back from 2 and a half weeks staying in Nagoya.
I didn't travel too much, and when I did I was navigating in the car with a friend.
I ate out a few times but the majority of the time I got food from the supermarket.
I used Manga cafes for the internet quite a lot too.
I took £500 worth of yen over with me and I can safely say that if I didn't take the shinkansen to Tokyo and if I didn't take a taxi to the airport (I woke up late and missed the train) I could have easily survived on £500 and had money left over.
One thing I noticed is that you say you have a mobile phone in your luggage.
Is this a rental phone or Japanese phone that you have bought in the past?
I ask because your mobile phone won't work over there.
If you need a mobile you may need to rent one.
As I said I don't know how much this extra stuff you want to do will cost you, but maybe you can get an idea by knowing that I had more than enough money for 2 and a half weeks in Nagoya with £500 worth of yen.
I'm sure somebody will come in with a better answer soon though lol
