Which smart home system is suitable for our new building?

would you possibly go for F@H if the electrician doesn't want to do proper KNX (the 20,000€ is already a defensive price if F@H only costs half)

Or just a bit of wireless and done?

We don't have the biggest demands either:

We don't need everything fully automated
We can still press a few switches or give a voice command
What is important to us is controlling shutters (preferably automatic shading)
controlling some lights, e.g. by scenes
window contacts (preferably window handle position)
possibly with a weather station

Sockets maybe a few but that works well wirelessly (we want to retrofit sockets ourselves anyway, so convert a single socket to a double or triple socket or chase from one corner to another)

that's enough and actually

It's also not easy to master 2 or 3 systems perfectly in parallel. I also struggle when, after a long time, I have to leave my familiar automation environment and use another or older version.

But the customer naturally expects me to be perfect at it and not only perform at 75% because I have to think twice about many things. That's a fair expectation.

I planned a stainless steel doorbell with a gong. Then I get up, go to the door, and open it with my hand.
If I'm unsure, I look out the window first (from above or diagonally from the kitchen) to see who is standing there.
Like 200 years ago, I know... but I don't need a video for that.

Yes, I also don't know what's so difficult about looking out of the window. If you have a house where you're currently playing billiards in the east wing and have to cover 50m (distance and height combined) to get to the front door - okay. But that's probably not the case for most people. The only reason might still be to let the delivery person in when absent, but there are more reasonable means for that.

The only reason might maybe be to let the package delivery person in while absent, but there are more reasonable options for that.

I would never install a function in my front door that allows me to open the door for anyone, remotely, i.e., via the internet... You install security doors and RC2 windows throughout the whole house for a five-figure sum and then add a backdoor next to them in the form of a smart door lock costing a few hundred EUR... :D

Yes, me neither. But I find the wish understandable...

We want to have a video doorbell

We want to see who is at the door when we are not home (e.g. postman and can tell him to put the package in the garage (briefly open the garage door via app or bring the package to neighbor X)

Then we want to see who is at the door when we are in the attic, garden, or basement and tell him (e.g. the parcel delivery person) we are here and don’t run away after 2 seconds

but opening the front door when I am not home is definitely out of the question
at most when grilling in the garden, so you can open the door for visitors if you can’t leave the grill or something
but that is very rare