If there is one truism about gun safes, it's "buy a bigger one than you think you'll ever need".
I just bought a second, very large safe used on craig's. It was made in central California and is about 20 years old.
My first was a very good Cannon Patriot 30" model. The seller talked me into that from the smaller one I started looking at. I keep this one in the house with a dehumidifier rod.
Guns, especially my air guns, breed like rabbits, and next thing you know I was out of room.
This second safe is big enough for me to get inside. It is less secure than the Patriot, but the average person is not going to pry it open in any short amount of time. I was told it weighed 1000 pounds and have no reason to disbelieve that, after the three of us moved it.
I keep the high value items in the Patriot and everything else in this beast. Bolted to a slab, I don't think anyone is getting into it in a half hour, and it keeps little fingers and opportunistic burglars out. Pros will probably get it anyway if they think you have enough value to spend the time and energy.
Bolting it to the floor is a very good idea. Mounting a fire sprinkler over it is another. Anyway, I think I am good in the safe department for a while.