Good morning,
Having travelled with JY for over 10 years now (and done something like 23 trips all over the world), along with various other travel companies, the subject of how much money to take on any trip occurs again and again on the Forum.
Please remember that you have to allow money for tips! You will need to cover coach drivers, local guides, sometimes bus boys, and of course your tour manager. A lot of these people are not that well paid, and rely on tips. It is of course up to you and is not compulsory! In your final documents JY should give an indication on how much to allow per person per day.
Hope this helps!
Cheers,
Hils