Key Lock Box for Your Holiday Rental: Self Check-in Done Right, Without a Code That Never Changes

The guests arrive at 10 pm, the owner lives 80 kilometres away, and the neighbour is tired of playing key-keeper. That is why the code-operated key box has become the standard answer for holiday rentals and holiday homes. It is only as good as the way the code is managed, though. This article looks at what the guides for owners warn about and how a key lock box with changing codes deals with the problem.

Eight options for handing over a key

The owners' magazine (Vermieter-Magazin) from Traum-Ferienwohnungen, a German holiday-rental portal, lists eight: handing over in person, neighbours or friends, an agency or concierge, the cleaner or a property manager, shops and cafés as pick-up points, a key box, an electronic door lock and a smart lock. Handing over in person gives you contact and control, but it eats up time and ties the owner to the guests' arrival. Electronic door locks and smart locks need fitting to the door leaf, a power supply and usually an app.

The key box sits in the middle: a sturdy box on the outside wall, opened with a code, with the key staying on site. Its advantages, according to the magazine: flexible arrival times, low cost, and a code that can be managed from a distance.

Where key boxes let you down

The same guides also spell out the weak spots:

• One code for everybody. Whoever has had the code once has it for good. That is why Travanto (a German holiday-rental portal) advises changing the code regularly and passing it on in confidence only; the advice to "change it after every stay" turns up in every owners' magazine.
• The obvious hiding spot. Travanto notes that a key box mounted in plain sight can cause trouble with the insurer if there is a claim. The box belongs somewhere guests can find with directions but passers-by cannot.
• Cheap casings. Traum-Ferienwohnungen recommends looking at quality and user reviews when choosing a model. A box that can be levered open with a screwdriver protects the key from nothing but the rain.
• Codes being watched. Whoever uses the box at the front of the building is being observed. A keypad where the real code cannot be worked out from what was typed takes the sting out of that risk.

How the WardHub approaches it

The WardHub key lock box is made for changing users rather than a code that never changes:

• User code and master code. The owner holds on to the master code, and the guest is given a user code. The lock can be switched between changing and fixed users: in a holiday rental it runs in changing-user mode, for your own family on a fixed code.
• Guard against prying eyes. The keypad also prevents bystanders from reading off the real code.
• Weatherproof. Electronic PIN-code lock rated IP65, meaning protected against water and dust, with a powder-coated casing for indoor use and sheltered outdoor areas.
• Casing in 2 mm hardened steel, closed on all sides, with the bolt mechanism on the inside. Hardened steel resists levering tools better than stainless steel, which does not rust but bends more readily.
• Space for more than a single key. At 200 × 134 × 70 mm (external dimensions) it takes a key ring, a chip card or a mobile phone.
• Mounting through three fixing points on the back; wall plugs and screws are in the box. Power comes from three AAA batteries, no wiring needed.
• Insurance rating up to about 1,500 euros, depending on the insurer.

There is more on the construction in the article WardHub, the compact valuables safe, and all variants are in the category WardHub.

Step by step for owners

1. Before the guests arrive: Set a fresh user code and send it to the guest with directions and a photo of where the box is, plus a phone number for emergencies.
2. Arrival: The guest opens the box, takes out the key and shuts it again. No meeting, no hanging around.
3. Departure: The key goes back in the box. The owner or cleaner checks on the next visit that it is there.
4. Once the guests have left: Change the code. The previous guest cannot get back in, even if they have shared the code with someone.
5. Where to put it: Not beside the front door facing the street, but in the yard, at the carport or behind the entrance, where it can be found with directions.

In short

The key box is the simplest form of contactless check-in. The risk is not in the idea but in the fixed code and the thin sheet metal. A key lock box with user and master codes, a guard against prying eyes and a hardened-steel casing does away with both. Everything else is routine: a new code for every booking, the box out of sight, a number for emergencies.

Sources: Traum-Ferienwohnungen Vermieter-Magazin, "Schlüsselübergabe für Ferienwohnung: 8 Optionen für Vermieter" (06/2020) · Travanto Vermieter-Magazin, "Schlüsselübergabe bei Ferienwohnungen: persönlich oder digital?" · Product details: product page WardHub 70101, diadorn.de, as at 02.10.2026.