At Buffalo Exchange you just show up with the items, they go over them and take the ones they like. And they give you a reason why they don't take the rest of them (e.g. "out of style")
They either pay you cash (30% of what they will sell them for) or give you store credit (I think it's 50% of the price they will sell for).
They tend to like hipster stuff and what's currently in fashion better. They take shoes too. Generally they are picky, but polite and pleasant.