I already expected that, with electrical questions it always goes in this direction. ;-)
Through my family, I can do quite a bit of the electrical work myself, but not on KNX and the like. Time is the problem here. We have already thought about what we want and implemented it as follows:
In the north area of the house (stairwell, bathrooms, hallways, entrance area) as well as in the storage basement and laundry room, motion detectors are used for switching. In the bathrooms and upstairs hallway, in addition to the presence detector, there is a relay circuit (Homematic) for dimmed lighting in the evening. In the south in the living rooms, we see no benefit in automating the light. We tried that in the apartment; it takes at least 3 years of living there until it fits the way you want it. Here, we have planned 2 separate light sources in each room, with two-way switches in large rooms. In the dining and living rooms, there are additionally dimmers. Roller shutters are controlled via Homematic (easy to handle and good for integrating sunshine and balcony door opening, etc.; also advantageous because they can be operated directly on site). Additionally, some small gimmicks.
Cabling from the electrician, motion detectors, dimmers, and roller shutter actuators from us.
Costs gross:
Automatic switches Busch Jäger 57 euros each
Roller shutter actuator Homematic approx. 60 euros each.
Dimmer with rotary knob Busch Jäger 50 euros each.
That means a 1,700 euro surcharge for automation. The buttons alone cost me that with KNX. Also, the extra wiring and extra control cabinet, the KNX motion detectors are much more expensive. Of course, KNX can do more, but do I need that?
Heating and ventilation run automatically without the need for regulation.
We are very happy with that. If I want to automate living rooms later, I will replace switches with Homematic actuators. If Homematic no longer exists in 10 years, I’ll just take the successor.