2nd Street NOHO
Did you go through a hypebeast shopping phase? Haven't we all! 2nd Street specializes in one-of-a-kind, unique (AKA Supreme) items.
The West Coast based re-seller is the new name in the game and has two locations in New York - one in Chelsea and one in NoHo. The selling process is pretty standard, you just bring your items in, show them your ID, they'll choose which ones they want, and then you're walking out with cash.
Unlike most other boutiques, they do not publicly disclose the methodology behind their buying pricing, so feel free to ask if you could get more for something.
[Photo via @2ndstreetusa]