You also need at least 3 people in the kitchen and6-8 to set up, serve and clean up the party.

Baked Ham 80#- bone in, 65 pounds at most
Baked chicken breasts bone in/marsala mushroom sauce (100 breasts)- small pieces- no more than 30 pounds boneless chicken
Potato salad using 40# potatoes - OK
baked beans 6 #10 cans (recipe found here)- 5 plenty- skip the meat so that vegetarians can eat
green beans almondine 35#- 25 plenty
pasta salad 6 pounds pasta (recipe found here)-OK
mixed greens/strawberry salad 30# way too much, 20 at most
sliced watermelon (3 whole seedless)

You need an appetizer table:
Before the Buffet; Why You May Need an Appetizer Table
A self-catered buffet is a real challenge to the organizers, and things don't always come together as smoothly as hoped. By planning and setting up an appetizer area or "nibble table" which is ready when the guests begin to arrive, the cooks and servers have time to complete the arrangement of the dinner buffet. This is especially critical if there are children among the guests, or there is a wait before dinner, as at a wedding reception.

This does not have to be complicated. Three items, plus a punch, or two if one is alcoholic, are sufficient. Typically, include a fruit tray, a cheese tray and an attractive dip or spread; or you can go with a dinner theme such as TexMex with chips, salsas, Texas caviar and guacamole; Italian with bruschetta or antipasto; maybe shrimps or other cold seafood, if budget permits.

One appetizer service area One serving area is needed for each 100 guests.