Which router for our new building?

We bought the house and land from the builder.
We cannot change the house and exterior color so that the development area has a uniform style.

Inside, we can choose most things freely.

Unfortunately, I don’t have our floor plans on my phone, but here are floor plans that are exactly the same as ours.

The right half in the floor plans.
I am traveling for work, so I cannot scan mine, but they are exactly the same.

The right half on the floor plans

However, the staircase in the attic studio belongs – although mirrored – rather to the left. I don’t see any obvious spots for sub-distributions, so all the patching will probably have to take place centrally in the connection room in the basement, and ceiling access points probably in the ground floor and attic respectively in the middle of the corridor roughly opposite the stairwells.

Yes, I will definitely do all the connections centrally in the basement.

In the ground floor, do you mean the access point on the ceiling between the dining table and the stairs?
On the 1st floor in the hallway on the ceiling and in the attic studio simply in the middle of the room (1 access point should easily cover the approx. 35 sqm room alone).

Do you think 1 access point in the middle is enough on the ground floor or should I do 1 in the kitchen and 1 in the living room?

In the attic, you could also do 1 access point via [Inketor] and put it on the wall, right? The ceiling is difficult because of the sloping roof. There is enough LAN in the studio.
(Can I also go from a LAN switch to an access point via [Inketor] or does it have to be without a switch directly?)

According to the developer, we will build the electrical planning with the electrician from scratch.

The standard includes, for example:
11 single sockets
13 double sockets
1 lamp in each room/hallway
5 satellite connections
No LAN cables
Doorbell system
1 lamp in front of the house and on the terrace
1 switch for each electric roller shutter
And individual room controllers for underfloor heating

We can freely determine the positions of all the connections.

All connections, such as LAN cables, additional sockets, and so on that go beyond the standard, will of course be charged.

What I can recommend to you ad hoc (we are exactly one step ahead – already have an offer from the electrician): Choose LAN double sockets. Additional cost for us is about 20% compared to single sockets.

Yes, double sockets are planned everywhere that are free for any devices. Sometimes, however, there are still some devices connected to them that have LAN. For example, Xbox, Nvidia Shield, receiver, maybe also TV. That’s why I would put a small switch there, for example a 5-port, but of course still the double socket.

Why injectors? If you have a POE switch, you don't need injectors. The cables all run to the patch panel anyway, where your switch should also be.