This will give you all info you need.
Gun Safe Buyers' Guide
One of the best safes are the fort knox. They are expensive because they are amazing.
But if you want to go more modest at least choose one with 10'gauge or 11'gauge body and double door panels. It is not the thickness
of the overall door but how much steel is in the door and the quality of the locking system. Most new brands are chinese garbage that
look like huge thick doors made of composite. all stack on, the cheaper liberty, and countless others.
Go with a US made not just because they are made here but because they are better made with more steel and better quality and
better welds.
Champion has a nice one made with 11 gauge.
Gun Safes | Home Safes | Fireproof Safes - Champion Trophy Gun Safe
Also do not discard browning hunter model made in the US also 11 gauge with very nice finishing and even support int he doors
to stack scoped rifles...
Hunter - HR26, Hunter Series Gun Safe, Browning Gun Safe Product
I would not go any lower than that but if you have to stick to US made liberty or champion or even a browning. Some made in mexico
but far better than some of the chinese ones that are more expensive look more expensive and bigger but they are pure garbage.
I mean, if you want them for something else than keeping the firearms away from kids and to actually protect your investments.
Bolt the safe to the ground and consider one larger than what you think you need unless you are open to have a 2nd safe, maybe
a better one for your more valuable investments.
A good safe is an investment not an expense.