Depends on whether you will have any off-site storage as well...?
I think you're very smart...small is beautiful! Less overhead (especially rent!) and other complications. Hope you've already found your space because at least in my experience, small spaces that work are very hard to find. Focus on quality with a simple menu. As for the organization, start thinking compartmentalized so everything has it's own space. Sometimes, I find that inspiration can come from unexpected places. If you haven't encountered this already, check it out. http://www.tumbleweedhouses.com/ Maybe it'll prompt some ideas.
Just find nearby storage. I rented a garage at an apartment complex that's four blocks from my shop. It's become my habit to stop by the storage-garage each afternoon on my way home and get the stuff I'll need for tomorrow. It will also be helpful if your suppliers can make frequent deliveries, thus allowing you to order in smaller quantities, (but more frequently).
I think you're smart to do this. It makes more sense to pay the high rent only for the square footage you need for a good retail location and pay less rent, per foot, for your storage space.
You might find the back seat of your vehicle becomes a semi-storeroom. I know there's days when I haul around a case of napkins, or something, for an extra day or two until there's room in the shop's designated space for that item. I'm kinda anal about where stuff goes and this helps me keep supplies at a minimum without running out.
Yes, I have been considering removing the backseat from my Jeep! =0)
i love my small store. i think it is a fantastic model and probably the most efficient way to make your cafe operate at maximum efficiency! keep your menu limited and strive to make the highest quality drink and you will be be in a great position!