From the start you need to decide your basic operational procedures, such as:
Food co-ops are not about profit, but they do have to put some mark up on the prices of goods to cover their overheads, such as the cost of produce, packaging, volunteer expenses, etc. This mark up will vary from one food co-op to another as overheads differ. It is important that you decide on your pricing structure by working out your costs first, rather than just trying to sell food cheaper than other outlets.
You also need decide how you are going to deal with all the other aspects involved in running your food co-op, including: