We are planning to open a village shop as a community co-operative. What is the best legal structure and can you advise the pros and cons of the various alternatives?

I was trying to find out the legal responsibilities and obligations of Housing Associations in general and under the Companies Acts, particularly in regard to tenants and in their wider social responsibilities. I tried looking it up on the web but there is not much in layman’s terms. So I would appreciate any summary and/or signposting to websites that explain this in a non-technical way?