I saw in a magazine the best way to store both potatoes & onions is in old (clean!) pantyhose! Drop one into the leg then tie a knot above it, then drop another in, tie a knot...and so on, then hang they from the ceiling in a cool spot. They said to remove them cut a slit in the side of each hole and then you can reuse the hose for more potatoes. It's supposed to keep air circulating around them and keep them fresher longer. Like the old adage "one bad apple spoils the barrel", I've always heard and believe one bad potato can spoil the whole bag, especially if they are kept closed up in the bag they come in, once one rots they're all close behind.

Not that I've ever done this, but it may be worth a try! I hate to buy more than a 5# bag because they just go bad before we use them. I try to keep them on the basement stairs because it's cool, but I'm not sure it helps!