I’m looking for open source or other solutions to manage a controlled RFP process. Specifically, I want 5000 vendors to be able to register with basic profile information, and then I want new customers to be able to submit RFP’s and watch proposals roll-in from the 5000 vendors over time. Ideally would like RFP submitters to be able to compare proposals from different responders side by side. Anyone aware of anything like this?