Abstract: This invention is a collaborative funding system which allows many people to work together to fund a project or to purchase a product or service. A computer system offers services to users, typically over the internet. Users may enter a new product into the system, contribute to a fund for buying a particular product or quote a product to sell it to other buyers. Once a product is quoted, the system chooses the best quote and offers the product for sale to the users. Buyers' funds are held in trust until the product is furnished. The system also provides a mechanism for the seller to build the product in stages and be paid for each stage. The system allows a negotiation between buyers and seller to determine whether the product or stage is complete.