@DorianGray
Ask your "surgeon" just 2 questions:
1. Who harvests and who implants the hairs?
2. What is the typical normal hair density at the hair line and what percent of that you can achieve with a single procedure, without a large percent of implanted hairs dying?
The answers will tell you volumes. Do not expect a natural hair line from a single procedure, just an illusion for a natural result, unless you are fortifying within the limits of an already existing hair line. The result is worse if you want to create a lower hair line (that's why they rarely do it), not just a little fill in the corners - then you are guaranteed the fake hair-plug look with only a single procedure.