I've got an event coming up for 175 and I'm cooking about 105 pounds of butts. I think that's probably much more than I need. But leftovers are always good and running out of food is ALWAYS bad!
I have a chef friend who cooks lots of butts for Farmers Markets and gets 70-80% yield. He brines them first - maybe that helps.
Shoot me an email and I'll send you a catering calulator that I use.
Have fun. Contact me anytime if I can help.
Roaring Fork BBQ :-D
Modified Traeger 075