Meat Amounts

Some unknown variables, but one of the best ways to is simply to know your price per pound of the meats, how many that roughly serves (same for sides), tell the client these numbers and then ask the them how much they want to purchase.

You've catered before so you know your yields on the meats after cooked. It's good you said you know your clients because it helps to know if its couples or the high school football team. Generally I found they eat on average 6-8oz of protein and 4-6oz each of sides. Ribs are tricky, it helps if you serve vs all put out on the buffet, people will load a plate with more than they could ever eat. I don't think you will be surprised about consumption since you've done buffets with two meats before. Jason had excellent advice, absolutely good info to have while planning.

1/3# each meat and 3 bones per person.