Oleg ,
You already know each person has a different PH level their body gives off - some folks just "touch and rust". You also know Stainless - just "resists" rust - it will rust. I'm sure you are not storing guns in cases.
Now we share similar climates ( TN , AR). I use the $4 "Sack Ups" for a variety of uses. For instance Citori 3 bbl set I took 2 SU and cut in half ( giving me 4 ) Receiver in one, a bbl in each of remaining 3 , before going into Browning Hard case. I wiped off before leaving range/ hunt. Heat and humity or Freezing cold , I never had a rust problem - even if it took me a long time to get home...or I was traveling. That Citori is the ONLY gun I ever stored in original gun case - in conjuntion with Sack Ups....granted - "storage" defined meant it spent more time being used than anything else.
That 870 , I break into two pcs for Carry in my 'no name' baseball bat carrier ,[ Steve must be headed to batting practice ] Sack Ups and I was beat when I arrived home.... umm...I took stuff out of bag and set on counter when arrived home - I checked it later today....no problem.
I did actually clean my CCW I used when I arrived home....I did change to JHP ( traveled home with FMJs in gun and spare mags) but left the other handguns for today as well...no rust. The Blue 1911, KFrames... were RIG protected - I wasn't worried based on past experiences...so I put it off until today.
When I had a car , I used to leave guns in the trunk ( times were different - grant you) as did folks leave guns in gun racks in trucks....I mean through all the seasons....never knew when I was gonna shoot. I was required to keep a PG only SG in trunk , and there may have been a 1911 in there as well 24/ 7/ 365 ....no problems.
Granted the Sack Ups are treated...IMO the RIG gets impregnated as well and makes them better.
For Storage / Safes , all handguns are loaded { I keep here] I use cigar boxes to stack in the Safe , grips are exposed some when placed in a Sack Up first. Long guns are unloaded - placed in Sack Ups before being place in Storage / Safe.
I basically keep stuff off site .I keep CCWs here, sometimes a shotgun. For security - " what appers to be - ain't - what ain't is. Apt living with exterminators and such... What guns?
I have been invited by folks to teach me Fiream Safety and teach me to shoot...I dunno about this gun dealie * smirk* I reply .
HTH