as nerd said, they get stuff sold or traded in and they re-sell. They have the best deals and the best trade in values so do keep them in mind.
Its rare for them to sell them. They sell whatever comes to their store. Luckily all their stores aren't that far from each other. You can call each store by googling the number. And ask if they have any in stock. But the store is probably the cheapest around so i recommend.
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