I would imagine they take the full amount and reimburse if you cancel within a certain timescale. If we had a responsible person(longshot I know lol) to handle the first ten bookings and give the money to MSV then that would be sufficient for their discount.
The kit is, zip together leathers, the zip must go all the way round, boots, gloves, helmet.
If you want to do it, take the morning sessions steady getting to know the track, and speed up gradually.
Take advantage of any instruction available, don't try to go over your limits, ride within them then you'll have some spare concentration if someone does something unexpected.