Need Advice on How to Choose a Surgeon?

I was thinking of getting a FUE hair transplant. I was hoping those that have been through it could give some advice on the following. Thanks for your help! How do you know/verify that the specialist delivered on the number of grafts that he charged you for? How many hair follicles should be in a graft? What is an optimal number of hair transplant procedures done by the specialist?

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