Who opens the door when you are 3,000 km away?
Nobody, unless the answer has been organised in advance. It is the first thing an absent owner discovers: a property cannot be held from a phone. A leak has to be seen, a lock has to be changed, a meter has to be read, an arrival has to be met — all of it requires somebody inside the house, the same day.
The most common arrangement leaves a single set of keys with a single person. It holds as long as nothing unusual happens, and stops holding the day two things happen at once. With us, keys are inventoried, at least two people know each property, and every entry leaves a written trace.
It is not a question of trust but of availability: the most devoted person in the world cannot be at their own job and at your house at three in the afternoon on a Tuesday. An organisation can.