I remember my dad modifying agreements for all sorts of things, back before it was legal a tenant was caught growing weed.Well its like this, if they put it in the lease and you are concerned, which for arguments sake somebody could be and I think the OP is if he asked - options are 1 - take apartment and sneak around, act wierd and stay up at night worrying about it 2 - pass on apartment that is otherwise what you want 3 - ask to modify the lease agreement and try to solve your problem openly.
I choose #3. Most landlord types are gun owning types and my guess is when they look an upstanding citizen in the eye its not the gangbanger or junkie they had in mind when they wrote that clause. You could even lie and say you own 3 shotguns for skeet shooting and that suffices for providing bare minimum information that even a libtard might accept, if you get an OK now your safe, gun cases etc etc can be spotted and you are in the clear.
I rent at the moment and in a smallish place there is no freakin way I could attempt to hide gun ownership - the safes once I got them in, sure nobody would notice fixing the water heater but the ammo, parts, tools, holsters, cases, boxes, mags, shit laying around I don't even notice haha no freakin way. But my landlord doesn't GAF, he carries himself and we talk guns.
my dad made him clear it out. That weekend my dad upped the electrical system and put fire retardent sheet rock in the basement. When I asked why
They will most likely do it again amd at least they wont burn the house down.