I'm also interested in hearing people's experiences with this!
Julia, may I ask about the current costs you have noted?
My initial thoughts on costs are
Direct
Coffee Machine
Grinder
Cups, cutlery etc
Food Wastage
Indirect
Accounting s/w and/or personnel.
Company registration costs (we have these in the UK, most likely there will be some in the US)
Staff Costs
Maintenance of machines (+ contingency for breakdowns etc)
Building Maintenance, Bills & Cleaning
Building works
(Future) Expansion costs
Advertising
Website
Hard truths: If you don't currently have a customer base or interested groups I'd consider this a J-curve business i.e. lots of money spent before returns are visible ...- if anyone is making a profit from a coffee business, please let us know how long it took to break even.
tips from other business ventures (you may already be doing this) - I'd highly recommend getting your business on google maps, gumtree (craigslist US alternative*), and other sites. Google was hugely helpful in getting customers through the door for my former business (tennis racket restringing). One thing I found got repeat customers was giving a 10-20% off coupon. Ensure you ask for reviews! - it feels weird but will ensure you're seen on maps and new people come. You can also start a google business site (which was free, I imagine it still is?) before you pay for a complete website.
Although I haven't started a coffee business I hope these tips are helpful
Rooting for you Julia!
Coffee_Mad_Man
EDIT: *I keep forgetting US don't have gumtree but craigslist!
PS - leverage your facebook friends, start a facebook page and ask them to like it; plus join facebook coffee groups too - again this is just a suggestion.