To register as a vendor and view current bids, please visit the Purchasing Services webpage. The City of Orinda is seeking proposals for Construction Management Services for the.This Contract is made in Contra Costa County and is governed by, and must be construed in accordance with, the laws of the State of California. E. Proposal Expenses. The following is a listing of various bid postings. Click on any of the titles for the details on that particular bid. CCTA uses PlanetBids for the procurement process. Visit PlanetBids to sign up, download the RFP and other documents, and submit proposals.