A lot of folks around here will low ball you on pricing saying "it's a yard sale". You will need to decide if you want to sell things for low prices and get rid of them or if you don't care if you've got them left over. You might do better with a charity sale, I've never run one, but for all the sales I've run, even with nice antiques people will not pay big prices.
I hope this isn't true for you and that you do well. If you can do brownies as well as the drinks, that's always a big seller.