I am going to add a pizza buffet this fall and I have a few questions. The buffet will have a salad bar, hot food section (pastas) and enough room for about six medium pizzas. First question, what kind of a margin can I expect to get from each customer eating at the Buffet? I have about fifty seats in my dining room. Is this enough seating to make it profitable? If anyone else out there has any other suggestions. I am all ears. Thanks Steve
Just my 2 cents…(keep in mind we have never done a buffet) You will probably only be able to fill your restaurant to capacity 2 times during the dinner/lunch hour(s) That is if all goes well.
I wouldn’t consider a buffet unless I had at least 100 seats.
If you do do a buffet, I would do a high end type buffet. Go for quality rather than quanity. You only have 50 seats so you aren’t going to go through product like crazy. Charge enough and put out great food. Not your typical buffet “crap”
Again just my 2 cents.
Figure out which items have the lowest food cost and position them accordingly. There’s a reason you’ll find the salad at the front of the buffet and pizza at the end – fill 'em up with the cheap stuff 
Success in the buffet business is all about volume . . . you gotta move bodies in the door to pay the prices. If you cannot move enough bodies, then you will lose money. If you move extra bodies, then you score bigger margins on the last 20 people than the first 100.
The math seems to be about figuring how much food to put out, holding times, consumption rates and WASTE. The last item is the insidious killer of buffet operations. Nasty, stale food will drive off customers, and throwing out food eats money. The margin will depend on the price you set and the food you sell. Really. Low margin food products will get a better profit margin (I know you know that) . . . and you have to figure in waste to the cost of goods and reduce from profit margin.
There are some really good threads from last year in the SEARCH up above. Look for buffet and the like. Lots of folks contributed brilliant info.