S.C. Code Ann. § 57-3-180

All persons to whom open-end permits are issued shall file with the Department of Transportation before the twenty-first day of each January, April, July, and October reports showing the number of trips made during the preceding quarter ending on December thirty-first, March thirty-first, June thirtieth, and September thirtieth, respectively, the dates of the trips, and other information the department may require. The fee of ten dollars a trip, required to be paid pursuant to Section 56-3-710, must be paid to the Department of Transportation with each report filed. However, the fee for additional trips of less than twelve miles distance made under the open-end permits is one dollar a trip. Persons to whom open-end permits are issued shall maintain full and complete records of all oversize mobile homes, modular home units, or utility buildings moved, the records to be open to audit and inspection by the Department of Transportation and the Department of Public Safety.