My Friend and I are looking into Small Business Ownership.....is it worth it? Does it pay enough?

We are still brainstorming a few different ideas at this point and still need the full plan drawn up. But we are looking at something of a coffee shop/ deli type of place with moving into an online enviroment as well. I am or we are curious to is if smart for people to partner to own a small food service company. I know its hard to answer but we are just trying to see what the average income to the owners are for a business that is making money. We are trying to determine if we could make enough to survive until we can either expand to other locations or the online side of things take off. Any advice from someone who owns a small business in the food industry would be great. Or someone who has knowledge in this area. Thanks!