To choose the price of your events you can make an average of the amount that you spend on the ingredients you need for it and also consider the time that you are going to give to every event. (eg. for a market tour or a cooking class you can put a higher price because you spend more time on it).
You have to include all the beverages and the food in the price of your experience. If you prefer, you can also suggest guests to bring their own bottle.
Please keep in mind that your guests will pay 20% more than the price indicated.
For example, if you set the price of your event at 20€ your guests will pay 24€.