The Department for Business, Innovation and Skills has published practical information and advice on how to set up and run a collective purchasing or community buying group. It aims to help consumers combine their buying power to get better deals from shops and other suppliers. It includes case studies and is intended for groups of consumers operating on a not-for-profit basis.
BIS guide to community buying and collective purchasing (published 7th December 2011).
Posted by georgessengupta 
Cooperative toolkit 