I had the same concerns as the OP about having a safe (mine in a 2nd floor apartment). I ended up getting a
Frontier under-bed safe. Granted, the electronic part doesn't work anymore, but I use the key for all my uses. I store 8-10 handguns in there, and if I go out of town, I often pull the bolt from my Savage Mk II and the barrel from my shotgun and put them in as well. I bought mine from a local store, and can't complain too much, especially since it's wide base makes it easier on unsure floors.