A lot needs to be looked at to determine what you will need. How many meats will be served? What is the mix of people (men, women, children, age, etc.....)
Here are a couple formulas I use......
I figure on 50% yield out of bone in butts.... I too like leftovers........
serving size(ounces) x guest count x 2 (for 50% yield) = total ounces needed / 16 (to get the poundage) = amount needed to purchase
4 ounces per person - 4 x 200 x 2 = 1600 / 16 = 100 lb to purchase
6 ounces per person - 6 x 200 x 2 = 2400 / 16 = 150 lb to purchase
8 ounces per person - 8 x 200 x 2 = 3200 / 16 = 200 lb to purchase
If I was planning on 1 sandwich per person I would either plan on 4 or 6 ounces per person. If you add coleslaw to the sandwich that will effect it as well. If you have multiple meats you can cut back on your numbers. If it is all men, might want to increase. If it is a high school football team, really increase the numbers.... that is where the guessing comes in...... if you have any questions feel free to contact me....
Jeramy