Request for Proposal (RFP)
The competitive method used when the agency knows the problem but not the exact solution, and can weigh factors other than price.
Where an invitation for bid asks for a price against a fixed specification, a request for proposal describes a need and asks vendors how they would meet it. Evaluation weighs approach, capability, service and cost together against published criteria.
For fleets it is the right instrument for services and systems rather than vehicles. Fleet management software, outsourced maintenance, fuel management and consulting studies are all things where the best answer is not obvious in advance and where price alone selects badly.
The trade is discretion for scrutiny. Because an RFP allows judgment, the criteria and their weights have to be published in advance and applied as written, and the evaluation has to survive a losing vendor reading it. Agencies that treat the scoring as a formality are the ones that end up defending an award.