Back-to-school costs sneak up fast. New sneakers, a fresh backpack, maybe a whole new work wardrobe for teachers heading back into the classroom. It all adds up before you even open the school supply list. If you’re new to secondhand shopping, cheap back-to-school shopping in Buffalo and WNY doesn’t mean digging through junk. It means walking out with name brands for a fraction of the price. We’ve got a whole shopping guides hub dedicated to finding deals like this year-round. Here’s exactly where to go, depending on what’s on your list…