Is it possible to leave a newly built apartment empty without mold?

Heating should not be a problem, you can adjust accordingly

Heated rooms and no ventilation accelerate mold growth.

In the new building, a few liters of water should accumulate each day even without residents. And that must be ventilated out!

You could task the janitorial service, which the new property management will hire, with airing out the apartment at least once a day.

Alternative: Control a drying unit with a hygrometer or timer and have the tank emptied directly into the drain.

Alternative: Control the dehumidifier with a hygrometer or timer and have the tank emptied directly into the drain.

I would do it that way. Devices with a hose cost about €200. Additionally, monitor temperature and humidity via the internet and clarify an emergency contact in case something happens. Occasionally airing out would still not be wrong due to other emissions.

Heated rooms and no ventilation accelerate mold growth.

When quoting, one should not always just quote individual fragments, that is bad style. In my post, it said that both are important.

When quoting someone, one should not always just quote individual fragments; that is bad style. In my post, it said that both are important.

I did not quote you because I wanted to reply to you, but directed my comment to the OP.

Sorry if you take something like that the wrong way and take it personally.