I know they take walk-ins for piercings.
If you go in today depends how big and detailed the tattoo is they can schedule you within this week even tomorrow it all depends on who the tattoo artist is and how busy they are and how big and define the tattoo piece and placement of the tattoo too.
They are usually booked up and give you an appointment to come back. But.....give it a try, nothing to lose. Ask for Tim, he's very very good. I have eight tattoos :)
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