(a) The Contracting Officer may, from time to time during the term of this lease, require changes to be made in the work or services to be performed and in the terms or conditions of this lease. Such changes will be required under the Changes clause.

(b) If the Contracting Officer makes a change within the general scope of the lease, the Lessor shall submit, in a timely manner, an itemized cost proposal for the work to be accomplished or services to be performed when the cost exceeds $100,000. The proposal, including all subcontractor work, will contain at least the following details—

(1) Material quantities and unit costs;

(2) Labor costs (identified with specific item or material to be placed or operation to be performed);

(3) Equipment costs;

(4) Worker's compensation and public liability insurance;

(5) Overhead;

(6) Profit; and

(7) Employment taxes under FICA and FUTA.

(c) The following Federal Acquisition Regulation (FAR) provisions also apply to all proposals exceeding $750,000 in cost—

(1) The Lessor shall provide cost or pricing data including subcontractor cost or pricing data (48 CFR 15.403-4); and

(2) The Lessor's representative, all Contractors, and subcontractors whose portion of the work exceeds $750,000 must sign and return the “Certificate of Current Cost or Pricing Data” (48 CFR 15.406-2).

(d) Lessors shall also refer to 48 CFR Part 31, Contract Cost Principles, for information on which costs are allowable, reasonable, and allocable in Government work.