CD Warehouse sells used CDs and DVDs. They have some new product -- I guess it's closeout stuff -- that is sold at below-retail pricing. The store has a pretty good selection of both new and old. I always check it first when I want music or a movie. I've never had a problem with a skipping or scratched item.
However, I don't recommend selling your stuff to them. The last time I tried to sell them some CDs, they offered fifty cents for each one. You'd get more for your CDs and DVDs at a yard sale.
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