Walter,
I think you may be confusing the contract types (FPIF, CPIF, etc) with some of the procurement documents (IFB, RFP, etc). Invitations for Bid, Requests for Information, Requests for Proposal, etc are used for the buyer to determine who in the market (the seller) can provide the product, service, etc. They do not equal a contract; they clear the way for the seller to bid on the buyer's project based on the established criteria. You may even see a bidder conference in some cases where numerous vendors will gather to try and secure the contract. Once the buyer picks a seller, the contract details are then worked out.
- Steven