To create my ultimate gun safe, I started with the Cabela's Outfitter 86 series, which holds up to 64 long guns ($1,750; cabelas.com), and augmented it with a few upgrades from Liberty Safe. These made the interior more efficient and useful. Some are must-have items. Others are good to have, depending on what it is you're using the safe to protect.

The EVA Dehumidifier recharges by plugging it into an outlet. When the crystals turn from green to orange to green, it is ready to go again. ($25)

Installing a Door Panel adds numerous pockets to store handguns, documents, and other small, valuable items. Cost depends on the size of the panel. (From $89)

The Magnetic Gun Caddy has foam jaws that grip a gun barrel and keep it from falling over. I use mine to prop up and hold a gun while I open the safe. ($14)

This Pistol Rack is an elegant way to store four handguns along with other items, like speedloaders, in the tray below. Barrels slip onto coated metal rods. ($35)

Liberty Safe Rifle Rods allow you to store more guns in less space. One end goes down the barrel. The other sticks to the shelf with hook-and-loop material. ($40)

The Under Shelf Pistol Hangers come four to a pack and suspend handguns securely with plastic-coated metal that goes down the barrel. ($20)

Multi-Mag has two magnets that are strong enough to hold loaded magazines or an empty pistol. They are rubber-coated to prevent scratches. ($30)

Manual dials are a pain. Once you go with an electronic lock, you’ll never want to go back. The lighted keypad makes it easy to open the safe in the dark. ($99)