What cost you the most nerves during the house construction?

you have 1000 Mbps internet and are satisfied even though only 250 Mbps come through the wifi? If that is enough for you and you do everything over wifi, you can also downgrade your plan. As soon as multiple devices are on the wifi, it drops even further… Install additional APs so that you have stable wifi that can also utilize your expensive plan.

You're right, I still have to do the test on the LAN. But it's basically clear that you don't get a 1000, right, or are there any in practice somewhere?

Vodafone has 1000 internet. You ordered that, right? What does the display on the router say? I only ordered 400/40. At my router, 435mbit arrive. I can access that everywhere in the house via wifi. But wifi can now (optimal conditions, not many devices…) do over 1000mBit. It is mainly about when multiple devices are on the wifi. When distributed over multiple APs, not only the reception and speed itself is better but also the load per access point is lower.

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Anyway, it was interesting to watch how the electricity later "shot through" from the opposite sidewalk onto our property. If you stood in the right spot on the ground, you could feel the vibrations and knew where the "shooting device" was at that moment.
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We had an empty conduit under the street. The main line is located under the (paved) sidewalk opposite. Therefore, the utility company routed the power line differently than agreed in the plans. Otherwise, they would have had to break up the street. But it was interesting to observe how the electrician tapped into the main line.

As a positive point, the utility provider also installed Vodafone and fiber optic empty conduits into the house right away. Even though we hadn’t ordered (or paid for) it.

What does the display on the router say?

I am just realizing with shock that you cannot check that on the Vodafone cable modem/router. Or I am too stupid to find the option. Do I really need a better modem/router now to read out the information?

No, even the simplest cable box shows that. Log in on the web interface and then check under Internet or Connection. It shows the connection there.