S.C. Code Ann. § 6-24-20
As used in this chapter:
(1) "Cost", with respect to a project, means:
(c) other expenditures of the joint agency incidental, necessary, or convenient to the acquisition, construction, implementation, reconstruction, improvement, enlargement, or extension of a project.
If a project does not involve the acquisition or construction of a facility, "cost" includes all costs of the undertaking or funding of the undertaking. In either case, "cost" may include those administrative expenses a joint agency considers appropriate.