Okay, let’s tackle this. So Mark Shaffer has a strong background in gas and subsea engineering, which is a specialized field. He also has supervisory skills, which indicates he can lead teams. Location is Greater Houston, which is a major energy hub. According to national averages, experienced professionals in these fields can command hourly rates in the $100–$200 range. Considering his expertise and supervisory skills, I estimate his rate to be around $125, which is on the lower end of the range but still reflects his value to clients.