You have some humidity but no salt air to deal with. If you have a dehumidifier in your safe, I think a light coat of silicon or something similar would probably take care of the barrel and action. If the guard screws aren't torx or socket head, you'll need a gunsmith screwdriver to remove them so they aren't damaged. The bore should be cleaned thoroughly, then protected by a good coat of oil or grease. If you take the gun out to handle it, I wouldn't return it to the safe without removing the fingerprints (which will cause rust spots) and restoring the protective coating. If you gunk the gun up too much, there's a chance the gunk might seep into the stock and damage or discolor the wood so don't overdo it. If you want to be extra careful, store the rifle muzzle down to help keep lubricants away from the stock. I would wax the stock exterior but I don't know that it's really necessary. I've bought military rifles that were stored for decades in cosmolene, a thick grease. It is nasty to clean up and darkens the wood but it does protect against rust. Just my 2 cents. Since this is an investment rifle, get some expert advice!