Costs necessary for the upkeep of real or personal property, including District property, unless otherwise provided for, that do not add to the permanent value of the property or appreciably prolong its intended life, but keep it in an efficient operating condition, shall be allowable as follows:
Expenditures for plant and equipment, including rehabilitation that is capitalized and subject to depreciation, shall be allowable only on a depreciation basis.
Service and warranty costs that include costs arising from the fulfillment of any contractual obligation to provide services (such as installation, training, correcting defects in the products, replacing defective parts, and making refunds in the case of inadequate performance) shall be allowable when consistent with the terms of the contract and when the allowance of the costs would not result in a double payment by the District for correction of defects.
D.C. Mun. Regs. tit. 27, r. 27-3322