In my experience, the length of a hair transplant session can vary depending on the technique used and the number of grafts being transplanted. For example, with the FUE technique, which I had done, a session can last anywhere from 4 to 8 hours. This can also depend on the skill and efficiency of the surgeon and their team.
The cost of a hair transplant can also vary depending on the location and the clinic you choose. I had mine done at a reputable clinic in a major city, and it cost me around $5,000 for a session of 1,500 grafts. Overall, the process was worth it for me, but do your research and choose a clinic with a good reputation to ensure a successful outcome.