Since it may be self serve, it sounds like you are donating the food to attract people to the auction. ? Will people need to pay to serve themself? You may want to consider selling a sandwich platter with beans and slaw, maybe some chips and donate the money to the fundraiser. Folks will galdly pay if they know the money is going to the cause. Then 4oz per sammie will be plenty. Keep the price reasonable even though it is a fundraiser for their friend. Also, maybe package some 1 and 2 pound bags and sell/auction those to help raise more money. If you auction 1 butt, only one person walks away with good BBQ. With 50+ folks, you can sell more than that (not everyone will wants 5+ pound, but want some to take home). Just a thought.
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