Hi vikdream! I hope the weather in BCN is warmer than it is over here!
To answer your question, yes CTC cover all accomodation during the training course. During the initial training in Southampton you will house share with the other cadets. I think some also stay at their training "mansion" in Dibden. Then out in New Zealand you get to stay in their dedicated accomodation block "Clearways". Then it's back to house sharing in Bournemouth for the IR stuff.
The £10,000 is what is recommended by CTC for food/drink/social activities. You may spend more or less than this. I'm certainly hoping to spend a lot less than this and use the saved money towards my Type Rating.