Planning electrical systems to be future-proof

I wanted to ask how big the control cabinet should be We are building without smart home (so no KNX)

Without a bus, your control cabinet is actually not a control cabinet, but a meter cabinet, fuse box and/or a distribution board. And it should accommodate all RCDs, circuit breakers, possibly AFDDs and meters that you need. I have not yet heard of any plans to expand the RCDs or circuit breakers later on. AFDDs are sometimes retrofitted or changed from RCD+circuit breaker to combined RCD+circuit breaker. And meters are sometimes retrofitted for e.g. photovoltaics, e-cars, ...

Thank you for your answer

ok then this is the meter cabinet for us :D

Yes, photovoltaic will also be retrofitted later for us
and the ekey controller

I think the standard control cabinet should be sufficient and we don’t need to take a bigger one, right?

The electrician said that there is still 1 row free in the standard control cabinet (but I would ask again to be sure)

A thick power cable will be laid to the garage (5x6mm² or 5x10mm² I don't know which is better for us, whether 5x6 is enough or 5x10 would already be necessary) the electrician told me 5x6 is enough and for our neighbors with the same conditions they definitely need 5x10

A sub-distribution will then be installed in the garage and will supply the following things

Wallbox 11 KW (22KW needs approval and is exaggerated for a private household, right?)
Garage door
Sockets in the garage
Lights in the garage
Sockets in the garden

I think the standard control cabinet should be sufficient and we wouldn't need a bigger one, right?

Since there is no fixed standard, that cannot be answered. Having only one free row is really very little when a controller, a smart meter, and photovoltaics are to be retrofitted.

A thick power cable is being laid into the garage (5x6mm² or 5x10mm², I don't know which is better for us, whether 5x6 is enough or if it should already be 5x10). The electrician told me 5x6 is enough, and our neighbors with the same conditions definitely need 5x10.

6mm² is already quite substantial. 10 is often laid reluctantly because it is very rigid. Why are you so sure that the neighbors need 10? Your requirements with a few sockets, some lighting, and a small wallbox are not particularly high yet. Ultimately, it depends on the length of the cable.

The electrician recommended that to the neighbors. They don’t want to do much more than we do.

The neighbors might possibly install an automatic irrigation system with pumps (but those shouldn’t need much electricity either).

For a wall box in a private household, you should go for 11 kW, that should be completely sufficient, right?

I don’t have an electric car myself yet and therefore have little knowledge, I just want to prepare the power cable for the wall box.

Cable length should be under 20m, it’s only from the technical room up to the garage.

So you would say 5x6mm² is completely sufficient? 5x6mm² is already recommended for the 11 kW wall box alone (at least 2.5mm² but 5x6mm² is recommended).

In the garden, we don’t have any big consumers.

Only a robotic mower, lamps, and sockets, and possibly a socket and lamp in the garden house.

I asked the electrician again

The standard cabinet is a HV with 2 field distribution.
As an alternative, he can offer us a HV with 3 field distribution

Can you estimate better what would be sufficient this way?

That doesn't say anything.

What exactly should be included?