What should I think about before getting a tattoo and what should i get?

I am planning to getting me a tattoo to mark the change I will go through with the GBP surgery. Apart from my parents never wanting to talk to me again, what should I think about? How much is a one color tattoo, like a little dragon or something like that? Where should I put it? Does it hurt?

Any suggestion on what kind of tattoo I should get? I have no idea myself, but something that marks a new life, kinda. Perhaps a phoenix, something oriental, perhaps the date of surgery…