Okay, let’s tackle this. So Mark has a solid skillset in mobile app development, but it’s not extremely rare. He’s not a lead architect or a technical lead, but a solid mid-level developer. His skills are in demand, but not at the top end. Location is Seattle, which is a tech hub, but not Silicon Valley or New York. That said, the US tech market is pretty competitive. I’ll look at national averages for mobile app developers. According to Glassdoor, the average hourly rate for a mobile app developer in the US is around $75–$100. Considering Mark’s skills and experience, I’ll estimate his rate to be around $75 per hour.