So, if you are catering the gig, I am assuming you are supplying all the food and drink as well as all the soft goods. How about beer, wine, sodas, etc.? You need to know that as that is key. You need to lock in a menu so your responsibilities are clear and defined.
If you've got kids there consider:
1. Smoked mac and cheese. Adults and kids love this and make this in advance and re-heats really well.
2. Hot dogs are a kid favorite. As kids get a little older they like wings (so do the parents)
Just make sure you get clear expectations with the boss before the event.
You should be charging at least $15 per head or so...... at least around here.
Large BGE, Cold smokehouse, Kamado Joe Jr,
Santa Maria pit, Backwoods Chubby,
26.75" Weber OTG, Weber Performer, WGA
MAK One Star, Smokey Joe, Jumbo Joe Gold, Custom wooden handles for BBQ's made by Marty Leach (oh, that's me)