for roomate/child/fire/flood-proofing a couple extra handguns, this works fine:
It's nice to keep a handful of important documents as well, such as insurance papers, soc sec card, emergency cash, etc.
Someone could easily steal the whole thing, but as long as that's not considered likely...
Personally I hide mine, rather than try to bolt it down. it's inside a very used-looking small square ottoman under an ugly spare blanket.
I'm assuming quick-entry is not a concern, because you mentioned your EDC gun would likely not be kept in the safe.