Im in a similar situation. I am looking to start a vegetarian (healthy eating) cafe and bakery, as well. I have 15 years restaurant experience as well as catering, along with a culinary degree. I currently run a small baking business as well. (www.happycookingonline.com) I think the best way to go is to check out local businesses that serve similar menus in your area. Check out cafes or caterers that deliver and see what they charge and that will give you a bit of a start. Focus on what and who your audience is and ask around to see how receptive it would be? Im currently in that phase at the moment. We've been at the local farmers markets for3 years and have gotten a good response to our baked goods, so this year we are looking to showcase our sandwiches to see what kind of response that gets as well.

When it comes to the restaurant business its better to work in the industry to get and idea of what is needed to make a go so you wont have any shock. Believe me if more people knew how hard it is to do what i do they wouldn't be so keen on it. Don't believe the rock star chef hype of the Foodnetwork.

Good Luck!!
Glory lies in the attempt to reach ones goal and not in reaching it.