; (B) labor costs associated with the installation of such hardware, only if wages for such labor are paid at rates not less than those prevailing on similar labor in the locality of installation, as determined by the Secretary of Labor under subchapter IV of chapter 31 of title 40, United States Code (commonly referred to as the “Davis-Bacon Act”); (C) material costs associated with the installation of such hardware, including expenses involving electrical equipment and necessary upgrades or modifications to the electrical grid and associated infrastructure required for the installation of such hardware; (D) permit costs associated with the installation of such hardware