Build a terraced end house with an additional unit (GÜ) on your own

Don't skimp on the thickness of the empty conduit at the TV. An HDMI connector is large and not the only cable. I've seen a few times that a cable duct is plastered in. Don't forget the socket behind the TV.

Yeah, maybe a network cable as well. (My TV doesn't get internet access…) The socket can be mounted directly on the wall at TV height. But I can't think of more than those two cables.

I would definitely plan a wall lamp by the stairs. I would rather leave out the lighting in the footwell. I don't like it anyway. It always seems to me like the emergency lighting during a fire alarm.

My TV does not get internet access...

Such nonsense does not interest me - nevertheless I would not leave it out; simply because for a possible future owner nowadays it would be an anachronism, like without central locking, electric windows, and right outside mirror. Even just a reversing light is becoming rare nowadays.

Yeah, maybe network cables as well. (My TV doesn’t get internet access…) The power outlet can be mounted directly on the wall at TV height. But I can’t think of more than those two cables.

Cables for a sound system, additional HDMI cables for PlayStation, Xbox, receiver etc., antenna cable, cables for ambient lighting (LED strip)

The cable duct of course also provides space for a possible network cable, for those who want.

But the distribution function is of course taken over by the receiver, all cables come together there. Only one HDMI cable is needed to the TV, no matter how many devices.

And the speakers are located elsewhere and the cable also comes from the receiver. Who wants to use the sound from the TV?

But only if you actually use a receiver, right?