Re: getting half (or whatever) the fee as a deposit - I would love that. I tried to do that once and the gig got cancelled, no questions asked. Working with a school system, that's nigh impossible. Plush is right, working with a school system that doesn't respect or want an excellent recording is a dead-end road.
(I was not counting on that money to pay bills, but, certainly anyone would be disappointed at the loss of that amount for no good reason. I would have liked to use it on some more gear
)