a) Definition – A best value procurement means a contract award determined by objective criteria related to price, features, functions, and life-cycle costs that may include:
1) total cost of ownership, including warranty, under which all repair costs are borne solely by the warranty provider; repair costs; maintenance costs; fuel consumption; and salvage value;
2) product performance, productivity, and safety standards;
3) the supplier’s ability to perform to the contract requirements; and
4) environmental benefits, including reduction of greenhouse gas emissions, reduction of air pollutant emissions, or reduction of toxic or hazardous materials.

Different type of procurements have different type of protest procedures
Capital Development Protests see 44 IL ADC 8.2075
Office of General Services Standard Procurement see 44 IL ADC 1.5550
For Higher Education Procurements see 44 IL ADC 4.5550
Department of Transportation procurements see 44 IL ADC 6.390-6.440.

§ 1-15.86.
Responsive offeror. “Responsive offeror” means a person who has submitted an offer that conforms in all material respects to the request for proposals.

Responsible bidder, potential contractor, or offeror. “Responsible bidder, potential contractor, or offeror” means a person who has the capability in all respects to perform fully the contract requirements and the integrity and reliability that will assure good faith performance. A responsible bidder or offeror shall not include a business or other entity that does not exist as a legal entity at the time a bid or offer is submitted for a State contract.

(4) The contractor may not make a claim for additional costs or time because of a physical condition at the site, unless the contractor has provided notice to the governmental entity under subdivision (1).
(5) The contractor may not make a claim for an adjustment after the contractor has received a final payment under the contract.

y) Evaluation Team. Evaluation team members shall be determined by the State agency, tailored to the particular solicitation, and include, as appropriate, technical or other personnel with expertise to ensure a comprehensive evaluation of offers. Evaluation team members must not have any conflicts of interest or apparent conflicts of interest and must commit to the time to complete all evaluations and attend any necessary evaluation meetings. The State agency’s selection of the evaluation team members must be approved by the SPO, taking into consideration any conflicts of interest or apparent conflicts of interest.

§ 25-10. Authority. State purchasing officers shall have the authority to procure supplies and services, except as that authority may be limited by the chief procurement officer.

h) Multi-step sealed bidding. When it is considered impracticable to initially prepare a purchase description to support an award based on price, an invitation for bids may be issued requesting the submission of unpriced offers to be followed by an invitation for bids limited to those bidders whose offers have been qualified under the criteria set forth in the first solicitation.

(c) Public notice. Public notice of the invitation for bids shall be published in the Illinois Procurement Bulletin at least 14 calendar days before the date set in the invitation for the opening of bids.
Section 1.1585 Notice Time:
Each solicitation shall be published in the Bulletin at least 14 days prior to the date set for opening, unless a shorter time is authorized by the Code or this Part.

(j) Reverse auction. Notwithstanding any other provision of this Section and in accordance with rules adopted by the chief procurement officer, that chief procurement officer may procure supplies or services through a competitive electronic auction bidding process after the chief procurement officer determines that the use of such a process will be in the best interest of the State. The chief procurement officer shall publish that determination in his or her next volume of the Illinois Procurement Bulletin.
An invitation for bids shall be issued and shall include (i) a procurement description, (ii) all contractual terms, whenever practical, and (iii) conditions applicable to the procurement, including a notice that bids will be received in an electronic auction manner.
Public notice of the invitation for bids shall be given in the same manner as provided in subsection (c).
Bids shall be accepted electronically at the time and in the manner designated in the invitation for bids.
During the auction, a bidder’s price shall be disclosed to other bidders. Bidders shall have the opportunity to reduce their bid prices during the auction. At the conclusion of the auction, the record of the bid prices received and the name of each bidder shall be open to public inspection.
After the auction period has terminated, withdrawal of bids shall be permitted as provided in subsection (f).
The contract shall be awarded within 60 calendar days after the auction by written notice to the lowest responsible bidder, or all bids shall be rejected except as otherwise provided in this Code. Extensions of the date for the award may be made by mutual written consent of the State purchasing officer and the lowest responsible bidder.
This subsection does not apply to (i) procurements of professional and artistic services, (ii) telecommunications services, communication services, and information services, and (iii) contracts for construction projects, including design professional services.