Lighting and electrical planning in new construction

Ok, since there are several experts here right now, the question: In our house, we want to install one "WiFi transmitter" per floor despite the partially open construction style. So on the ground floor, I would have the router and on the upper floor a further "transmitter" connected to this router (to put it simply, so as not to misuse terminology). We will not have LAN connections, only cables from the router on the ground floor to the "transmitter" on the upper floor.

Option a) The existing Fritzbox on the ground floor and what would be a sensible model on the upper floor? Option b) What would be a rather straightforward, easy-to-implement solution for WiFi throughout the whole house for a "normal user"?

The utility room is located in a corner of the house and is enclosed by 17.5 cm brick walls. Can the router be placed there or is it better in the hallway/open area?

If we don't want a satellite dish, what is currently a sensible option to watch normal TV programs, like ARD, Kabel1, and other channels? Or is there a halfway decent-looking, practical satellite solution? Sorry for butting in, but maybe you are interested in this as well.

Very good question! I’m not sure yet if I can/want to afford KNX. That, of course, significantly influences the switch question!

Sure you want it, you just don’t know it yet. Tell me what you already know about it and what the wishes/needs are.

The utility room is located in a corner of the house and is enclosed by 17.5 cm brick walls. Can the router be placed there, or is it better in the hallway/open area?

It is the same in our house (currently and in the future). That's why there is no Wi-Fi transmitter there ;) but instead a central access point (hallway) on each floor. And of course, they are connected by cable to the utility room. Depending on the size and layout of the house, even a second transmitter might be needed if good coverage with 5 GHz is important to you. As for TV, we only use a streaming provider like Magenta, Waipu, ... although we still need to see whether this will remain long-term or will be discontinued in favor of using the respective providers' apps (ARD, ...) instead.

Oh yes, when it comes to the specific models, it depends a bit. AVM is quite easy to configure and offers good German-language support. If you can handle the model selection and are already using a Fritz!Box anyway, that would be the easiest option with the disadvantages already mentioned here, which may not be disadvantages for you. Otherwise, something cheap from China would be an option, either noname or TP-Link. For professionals, it can be Dell, Cisco, Juniper, ... Somewhere in between would be Ubiquiti, Zyxel, Netgear, ... I have been using Mikrotik for years and am satisfied, but the devices are not necessarily beginner-friendly. ;) For that, the price and performance are right.

Option b) what would be a rather down-to-earth, easy-to-implement option for WiFi throughout the whole house "normal user"

For a long time, ubiquiti was practically the standard for "better WiFi in home networks." But by now, with the same equipment, it is comparatively expensive (so more something if you want solid devices but not necessarily the top model, or if you don’t look at costs). Many features for little money, for example, TP-link and Grandstream APs offer, while the “professional” network suppliers like Cisco, HP, Juniper are in my opinion unnecessary for private use. For private purposes, I would make sure not to get anything for the house that can only be operated via cloud or with subscription licenses.

The utility room is located in a corner of the house and is enclosed by 17.5cm brick walls. Can the router be there or better in the hallway/open area?

Leave it calmly in the utility room. Together with a home server if available and KNX technology. The main thing is somewhere where no small children press colorful glowing buttons (my experience of the last few years) :D

Of course you want that, you just don’t know it yet. Tell us what you already know about it and what the wishes/needs are.

Yes, of course I want that! You’re probably right! ;-) So far, I have read up on the basics, both through books and here in the forum. Although I have even convinced my wife of the meaningfulness of the installation, from my point of view a KNX installation is still somewhat of a luxury compared to other items in the house construction.
However, I wonder if and how I can find an electrician who doesn’t immediately demand a 100% surcharge when he hears the word KNX. So far, we have planned €20,000 for the electrical installation. The question for me right now is whether I can have the basic KNX installation done with a 30-50% surcharge, which could then be gradually expanded together with the electrical company over the next few years. The priority at the start should be on the central bus wiring in my view. I want to be able to control lights, some sockets, blinds, and later also heating and ventilation through it. I don’t need visualization at first. Scenes can be added later.
Is that a reasonable plan? Are €20,000 even realistic for the planned standard installation? How do I find the right partner here in the countryside? So far, I have only contacted companies that are familiar with bus systems.