Hi Janice,
In terms of budgeting, this is a very personal thing. But there are some things to help. Firstly. All of your trips are included so no need to worry about carrying additional cash for optional excursions.
Looking through the itinerary you have many of the meals included and only need to budget for 2 dinners and your lunches. In an "average" restaurant you'll be able to eat for between 1000-3000 yen. Many of these will have set lunch menus at around 1000-1500 yen. There are cheaper restaurants where you'll be to get simple dishes like noodles for between 500-1000 yen.
While Japan historically has a cash culture, debit/credit cards are becoming more widely accepted but worth checking with the restaurant before you order. You should also be able to withdraw cash at an ATM in post offices and some shops (just let the Tour Manager know and they'll be able to advise the closest ATM).
The only other thing you need to consider is whether you purchase any souvenirs to take home and remember your trip by.
I hope this helps.
Kindest regards,
Julia