Instructions
Organize the magazines. Take out any magazine issues with mold, tears or damage from age. Set the magazines that are in good condition aside as potentially valuable. The oldest or rarest National Geographic magazines are sometimes valuable even when they are damaged, but magazines that are newer and widely available are often less valuable when damaged.
Go to National Geographic's Collector's Corner and click on the Collector's Forum. Write a post about which National Geographic magazines are in the collection and request information from the dealers about potential buyers or values of the magazines.
Pay attention to replies from the dealers. Newer National Geographic magazines are not as valuable as older ones, but value will often depend on whether there is someone looking for a particular issue or not. If none of the dealers are interested in the magazines, ask about potential buyers the dealer might recommend. Buyers are the collectors who often will pay higher amounts, especially if the magazine issue is out of print and not available.
Try looking on online auctioning websites. Websites like eBay are a good option to watch current prices, especially for the older collections that are more rare. Pay attention to prices set by others for collections and the years of the collections.