Below is a list of forms and information that may be required to complete a Request for Proposal Response. The complete bid or proposal must be submitted to the Department of Procurement Services before the date and time specified.Invitation for Construction Bid: Standard document that is used for advertisement on the Illinois Public Higher Education Procurement Bulletin website. Construction bids are publicly opened and read aloud on the established bid opening date. Prequalification. If checked, the 2 low bidders must file within 24 hours after the letting an "Affidavit of Availability" (Form BC 57), in. Please fill out and submit the relevant forms and their corresponding attachments: AE Consultation Prequalification Documents.