Based on the APICS certification, Stephen's expertise in supply chain management, and location in San Diego, California, I estimate his hourly rate to be around $75. This rate is lower than average for a certified APICS professional, likely due to the local market conditions and industry demand. APICS professionals with similar certifications can charge between $100-$200 per hour, but Stephen's rate is more in line with entry-level or junior professionals in the field.