Is there anything other than the large and small IC cores that resists lock change by people issued change keys?
Let's say for people who own homes for investment purposes lending their investment home in a college town and want to prevent addition of people not on the lease. (i.e. 3 bdrm house lend to3 tenants, but you don't want them adding a third person to attic room)
Even if the key can't be copied, with the common locksets, you can't prevent them from changing the door hardware since they can be removed with screwdrivers.
Is there such an option for both KIK and deadbolt? They both need to resist removal, so that they can't just avoid using the dead bolt with issued keys and changing the knob to off the shelf KIK set.
Basically it should be setup so that only those issued the key can lock/unlock doors and they be given no option but to leave the door unlocked if they were to add an unauthorized tenant and should resist duplication and lock change outs by common tools or the tenant key.