The average extra help salary at Riverside was $3,385 , which is 16 percent lower than the average salary for this job in California, but 4 percent higher than the national average for this job . Extra Help salaries at Riverside typically range from $1,166 to $4,567 (25th to 75th percentile). The highest reported extra help salary was $9,138. There are 46 employees at Riverside with the job title extra help.