19. (1) The reasonable costs of an investigation into a regulated industry, as assessed by the Commission and notified to the person who is to pay those costs, are payable to the Commission by—
(a) if the industry is a regulated industry by virtue of its infrastructure facilities being owned, controlled or operated by the Territory or a Territory authority—the Territory or that authority, as the case may be;
(b) if the industry is a regulated industry by virtue of the provision of services in the industry by or on behalf of the Territory or a Territory authority—the Territory or that authority, as the case may be;
(c) if the industry is a regulated industry by virtue of the ownership, control or operation of its infrastructure facilities wholly or substantially by a single person—the person who owns, controls or operates the facilities; or
(d) if the industry is a regulated industry by virtue of the provision of electricity, water or sewerage services or any other services wholly or substantially by or on behalf of a single person—the person who provides those services, or the person on whose behalf those services are provided, as the case may be.
(2) Costs payable under subsection (1) include any costs incurred by the Commission in obtaining the assistance of any other person, body (whether incorporated or unincorporated) or government agency.