Covers
Vintage comic book prices are mostly driven by the current popularity of the superhero and quality of the art and story. Condition can be just as critical in determining the value. The slightest bumps, bends and tears can deprive you of value. Place each important comic in your collection in its own PVC-free plastic sleeve. The sleeves can be secured with transparent tape, but be sure to attach the sleeve's flap to the plastic and not the paper comic.
Boards
A piece of cardboard placed inside each plastic sleeve will prevent casual damage during handling. The cardboard must be slightly larger than the comic itself and be both acid- and lignin-free, as these substances can cause the images in the comic to fade over time, according to Paper Craft Central. The insert also helps keep the comic from curling and supports the book when it is displayed or placed into a box.
Boxes and Cabinets
Corrugated cardboard boxes are made specifically to keep comics safe. These boxes with lids are also made of acid-free paper and allow for easy transport and long-term storage. Boxes prevent the possibility of fading due to light exposure. Depending on the value of the books and the desired display, you may consider a glass-enclosed case or bookshelf. Keep the display in a dry, low-light area.
Security
For the most valuable comics, owners choose to have their collectibles authenticated. Companies provide services to give you a record of what you own and its value, in case you ever need it for insurance purposes. Some vendors will even place comics into tamper-resistant cases, called "slabbing," to further secure the items and prevent damage or deterioration. (Reference 5) Also, if you're collecting a number of valuable comics, consider theft deterrents like alarms or monitoring services to maintain your investment.