The average custodial salary at Marlin Isd was $20,429 , which is 22 percent lower than the average salary for this job in Texas, and 38 percent lower than the national average for this job . Custodial salaries at Marlin Isd typically range from $20,280 to $21,146 (25th to 75th percentile). The highest reported custodial salary was $25,666. There are 13 employees at Marlin Isd with the job title custodial.