Consumer - to – Business (C2B)

In this model, a consumer approaches website showing multiple business organizations for a particular service.

Consumer places an estimate of amount he/she wants to spend for a particular service. For example, comparison of interest rates of personal loan/ car loan provided by various banks via website.

Business organization who fulfills the consumer's requirement within specified budget approaches the customer and provides its services.

It is also called a reverse auction or demand collection model, which enables buyer to name their own price, often binding, for a specific good or service generating demand. 

For example – ReverseAuction.com (travel, autos, consumer electronics) and priceline.com(travel, telephone, mortgages).