How many grafts do I need? (photo)

I’m 38 year’s old and I want to Do a hair transplant. I got multiple diagnoses from several clinics and they all been different..from 600 grafts dhi to 3500 grafts in FUE. I’m really confused between the huge difference in estimates and the value of the DHI method that was emphasized with one of the groups as superior to FUE, please help. I would like to know what is the best hair transplant procedure for my situation

First of all, there is no difference as the DHI method (just a marketing term) as is an FUE using implanters as most surgeons do. The people who push such terms try to create an image that what they do is different from everyone else.  But their DHI method is just FUE with Implanters, something most surgeons do (very disturbing to me). The area shown should take between 1300-2000 grafts depending upon the thickness of your hair shaft (fine for more grafts (2000), medium (1500-1600) or coarse for less grafts (1300).