Well, hold on to your seats... my T's policy is that you have to give 3 business days notice to cancel appointments! Weekends don't count!
So, if you have an appointment on Wednesday at noon - you have to let him know by Friday at noon to cancel, or be charged!
I *think* he might be flexible in case of sudden illness. I asked him about ice... I'm scared to drive when there's ice on the roads (we're in the south, so not that often) and he said that he'd let me cancel for ice

, but that I couldn't cancel if I just suddenly felt like not coming.
I've never seen anybody that required that much notice for a cancellation - usually it's just 1 or 2 days. It kind of sucks!