Give each key an accountable holder
A record might say “Store cupboard key B is with Jules; confirmed at move-in.” It does not need a photo of the key cuts or a precise public description of where an unattended key is hidden. When a holder changes, confirm the physical handoff with both people. If there are two copies, name them separately. “Cupboard key A with Rae; B with Jo” can be checked. “Keys with the family” cannot tell you whether one is missing.
Check changes of holder
When a key moves, record the person returning it and the person who physically receives it. Do not mark it transferred just because someone sent a message offering to drop it off. A coded tag can help identify the key without giving an unknown finder the exact address and door it opens.
If a key cannot be accounted for
Record the last confirmed holder and check the normal return location. Tell the person responsible for managing access if the key remains missing. Decisions about changing access belong to that person or the property manager. Keep codes, alarm information and precise hidden-key locations out of a generally shared inventory.