All purchases shall be awarded by one of the following methods: Competitive sealed bidding; Competitive negotiation; Small procurement procedures, when permitted by Regulation .14 of this chapter; Revised bids after competitive sealed bidding where all bids are rejected; Sole source procurement, when permitted by Regulation .11 of this chapter; Emergency procurement, when permitted by Regulation .12 of this chapter; or Intergovernmental cooperative purchasing as that term is defined in State Finance and Procurement Article, §13-110, Annotated Code of Maryland, and COMAR 21.05.09. The Authority shall select the method of procurement which in its discretion best meets the needs of the Authority.