yep need a cabinet bolted to wall - FAC airguns follow same procedures as powder burners, not too much of a job really and yes good standard household security.
if you want 2 fac airguns then you will need to apply for 2 slots and reasons why (one for dedicated NV is common) and 2 mods.
landowners permission from FAC passed land and then its straightforwards and not too much trouble.
cheap secondhand cabinets can be found on ebay