Abstract: A method and system is provided for managing multiple, simultaneous, multi-parameter negotiations for the purchase of products or services, such as agriculture products in an Online private contract environment. In the various embodiments, the method comprises a process to compile a database consisting of value-relevant product attributes and buyer demand attributes; a protocol to search, sort and display products and demand for products based upon these attributes; a protocol to aggregate products into “pooled” lots for sale; a protocol to allow sellers to negotiate simultaneously with multiple potential buyers on a private contract basis; a protocol to allow sellers to retain partial ownership in the products; and a protocol to produce a financial reconciliation upon delivery of the products or services.