Wow! Who knew my query would elicit such concern and responses?! Thank you all for your efforts, although there was not much in the way of price suggestions.
As it is, I'm doing this for the school because my boys go there and every single person at the school knows me, my wife, my kids. They know I'm a pastor who makes the best BBQ around. And they know I'm glad to do it because I will save them a boat load vs. some local bbq shack serving yesterdays q. They asked me to do this both to help them save bucks and to enjoy fresh, excellent bbq. As for cost, I'm looking for a reasonable fee that recovers me cost (projected at around $125) and something that respects my time commitment without seeming greedy, which I definitely am not. So, I think I'm going to settle for $3 per person, projected at 65, so a final of $195. That suggests my 2 hours of prep and 2 hours of delivery, clean up and supplies are worth, roughly, $70. I think it's a fair bargain for them, and a treat for me to do.
You've given me some thought, something to chew on (ba dum bum) for the future. I may look into that "layer of protection", although the phrase gives me a chuckle, in case I do make any move to cater or make some petty cash. Blessings, all, and enjoy National Smoke Day, as I like to call it.