The term “source to pay” (abbreviated S2P) refers to the general process used to contact one or more suppliers to “source” different solution proponents (options), prior to “paying” for them. There are many different forms of solicitation which can be used to receive information from suppliers. In addition, many source to pay processes involve competitive bidding processes between multiple suppliers before a proponent is finally selected by the purchasing party. On Tradogram, flexible request forms can be used to initiate a wide variety of solicitation processes. Suppliers are able to review offers proposed by the purchasing party, and provide a counter-offer with their proposed adjustments directly through the system.