I used to make my living as a construction electrician and had several big steel Greenlee brand tool boxes  with my tools. There is usually one in the back of my
truck all the time.
Price of gun safes has continued to rise, so I took one of my boxes and cut out a plywood rack for my guns, then filled in around the rack with polyurethane foam. After it was set and cured, I painted the urethane foam flat black.
The fit and finish on my Greenlee tool box/gun safe is good enough to protect my weapons, keep them locked and secure. It also has the advantage of handles and skids so it can be loaded into a pickup or bug out trailer to get to the remote retreat in a hurry. If necessary, I can load it with a forklift, or a chain hoist, or muscle it on with three other men.
Anyway, I thought you might be interested in my improvised gun safe.
The steel tool boxes can still be bought from Lowe’s [hardware store] for $199. Regards, – Lawrence, editor of SurvivingTheDayAfter@yahoogroups.com
JWR Replies: Thanks for that cost-saving suggestion. Just keep in mind that “portability” works both ways. It is essential that you secure your vault, box, or chest to a floor or a very sturdy wall, to prevent burglars from hauling off “The Whole Shebang.” Be sure to use heavy duty lag bolts!