I don't really run in proper "safe" circles and have no idea where to get a reasonable one without breaking at least the bank. However, when I was a kid I read stories about keeping food safe from bears by hanging it from tree limbs in sacks. I have two really big trees in my front yard. I figure if it works for food against bears, it's gotta be fine against people for guns too.(Kidding)
FWIW you can fit 40+ handguns into a 2.2 cubic foot firesafe without much bother, so long as you are willing to stack. The problem is when you say, "I haven't shot my .45c blackhawk in a spell, let's take that to the range this time..." and it happens that the blackhawk is at the back of the bottom shelf.
50 handguns is, when you think about it, not very many, and considering my gutter tastes they aren't worth much. If you consigned them or sold to an honest dealer you might net $25k on a good day, or if you trickled them out on gunbroker or did local F2F deals maybe $35k.
Given that I am fairly young and plan to continue buying, I'd like a solution that scales. I wouldn't be surprised if the total exceeds 100.
Compared to my collection 50 guns is a lot...I wish I had a 50 guns!! At the price you are at and since it sounds like your collection will expand in value and size, IMO a safe is probably a worthwhile investment, and it is worth getting a safe that provides more than just basic protection.
My opinion on getting the best security safe for a reasonable price is to sometimes go used if you find a good bargain. You can get used a true security safe for not much more than a new pimped out gun safe, and in some cases for significantly less. Often times you can also find really nice safes on Craigslist when people are either moving or have upgraded to a larger new safe and decided to sell the old one. One company that builds good gun safes for a reasonable price is Sturdy Safe. They are hideous looking but solidly built and affordable. With armor upgrades, these safes provide some burglary protection and protection beyond that of most other gun safes IMO (note that they are still not security safes.)
For your storage needs, I think a custom storage solution will best meet your needs since no out-of-the-box system is going to be best utilize space for your application. When I set up my main safe, I had a variety of items I wanted to have accessible and no out of the box rack system worked. I wound up using some 3M VHB tape, 1 inch pine boards, epoxy putty, dowel rods, and adhesive felt material. I made 5 shelfs in a safe that is about 60 inches high, with each shelf being variable in terms of height and width so it perfectly fits the items I want it to. If I had that many hand guns, I would probably build a custom shelf system to maximize the room with multiple shelves, each with handgun racks that would store the guns side by side/parallel with the grips facing outward to make removal of one easy and not requiring many others to be moved around. I would also use some of the LED strip lights with an adhesive backing from Amazon, given you can get a 300 LED strip now for like 6 bucks, and it will be as bright and look as good as many the safe light kits costing in the hundreds.
There are a lot of sites out there with used safes, but Lackasafe always has a huge stock of used security safes. Some items are priced better than others, but it is a good site to get a snapshot of options and pricing, and sometimes you get lucky and find a real gem. Local locksmiths often have used safes as well.
Just as a few examples, this is a TL-15 AmSec Steel Plate safe
http://www.lackasafe.com/products/used-safes-specials/used-amsec-tl15-high-security-plate-safe
this is a TL-15 equivalent Quantum composite safe with fire protection
http://www.lackasafe.com/products/high-security-safes/used-3020-quantum-tl15-high-security-safe
Those types of safes can withstand skilled attacks unlike most gun safes. As collection value goes it, it might be something worth considering down the road.
