gb, I've worked in several places like that and at one time was going to open my own. It's tons of work - are ya ready?! - but very rewarding, too.
Some things in addition to those already mentioned, are -
keep it simple, at least at the beginning; your enthusiatic customers are going to say, why don't you do this - or that - but you'll have to evaluate each one for it's merits and how it fits into your 'scheme'. IE, if you're doing a simple soup and sammy type menu, and someone says 'gee, it'd be great if you made your own ice cream'; sure, sounds like a great idea, and a real 'hook' to get folks in, but look at the extra costs, etc.
Visit as many like places as you can; talk with the owners, find out their joys and heartaches.
Talk with a food business consultant; I found one through the folks who do our accounting; their advice is invaluable, and they can guide you through a lot of pitfalls, even tho it costs you money.
Don't - EVER - EVER - buy equipment based on what the sales rep is telling you. Case in point - I was Kitchen Manager for a new place opening up, mainly burgers/sammies/pizzas (premade dough - yuck)/salad kind of place - BUT - they were opening for breakfast too, and the (@)#(*&$#)(*& sales rep told the owner we could toast our bread and bagels in the pizza ovens!!
I would love to shoot the breeze w/you on this - if you're up for it, PM me and I'll phone ya!