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...

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