48 CFR § 36.203 - Government estimate of construction costs.
(a) An independent Government estimate of construction costs shall be prepared and furnished to the contracting officer at the earliest practicable time for each proposed contract and for each contract modification anticipated to exceed the simplified acquisition threshold. The contracting officer may require an estimate when the cost of required work is not anticipated to exceed the simplified acquisition threshold. The estimate shall be prepared in as much detail as though the Government were competing for award.
(b) When two-step sealed bidding is used, the independent Government estimate shall be prepared when the contract requirements are definitized.
(c) Access to information concerning the Government estimate shall be limited to Government personnel whose official duties require knowledge of the estimate. An exception to this rule may be made during contract negotiations to allow the contracting officer to identify a specialized task and disclose the associated cost breakdown figures in the Government estimate, but only to the extent deemed necessary to arrive at a fair and reasonable price. The overall amount of the Government's estimate shall not be disclosed except as permitted by agency regulations.