Well if you are on a full time course then your full time attendence is indeed required by contract.
From your start date the FTO is planning aircraft and instructor availability for you over the next 13 months. Both of these items are expensive and cannot be left to stand idle whilst you ponce off on holiday.
Compassionate leave is always granted of course.
You want the lowest price - you have to be ready to fly as and when they have a slot for you simple as that.
On the matter of good questions try this.
"Hi, I have decided that I am going to train with either you or school X next door. Can you please supply me with the names and telephone numbers of a couple of your graduates please. School X has done this and their ex-customers seem real happy. I want to check yours are. Thanks."
After that perhaps try and get the CFI, Deputy CFI or other senior instructor as your assigned instructor prior to signing a training contract.
Good luck,
WWW