I think the problem with answering this is that there is such a wide variety of organizations, and we don't know anything about your situation. What size is your city, what kind of programs do you foresee, do you have a board of directors, do you have a space yet, etc.
There are very small shoestring budget co-ops that operate on volunteers and unpredictable donations, and there are very strong co-ops that receive a variety of grant funding and have well-defined programming and staff to match. The bigger it gets, the more you bring in and the more you can spend (more tools to buy, improvement ideas, website, part-time staff, etc.). Are you going to incorporate? Apply for 501c3 status?
You can look up any 501c3 organization's 990-N form via Guidestar to get an idea. These will be established organizations, with a board of directors and all the benefits of 501c3 status and established community contacts.