Number of network sockets; how to plan Wi-Fi in the new building?

"APs do not belong in the hallway area but where the most speed is needed."

if this is the optimization requirement. But if, on the other hand, you want to get by with the minimum number of devices for full network coverage, in many cases the hallway variant is simply the cheapest.

What good is network coverage if I have 5 GHz in the guest bathroom and only 2.4 GHz with full channels and possibly close to the range limit in the office and living room? Then you might as well use mesh and other solutions. If you are building new and also invest money in good hardware, I would at least want to use it.

Let me guess: you make your money from it, so not necessarily as a network admin but indirectly?

Put very bluntly: not every citizen needs high speed when taking a shit, for the wireless speakers, or the speed for 4K on the phone display while lounging on the sofa when the TV 4 meters away gets the same easily with a fixed connection.

And half a dozen access points, Cloudkeys and whatnot along with their connections, planning, configuration and maintenance is really something for freaks; in any case, this is NOT the normal case you can assume. If that’s okay for you or important to someone, then go ahead, please. You are certainly entitled to that!

But I haven’t heard such requirements from the questioners – otherwise they probably wouldn’t have asked the way they did. They are not interested in mesh, GHz, Ubi*wo, and you probably couldn’t convince them that a server rack makes sense either.

Like most people, they just want an easy-to-use network that works everywhere in the house without much fiddling, so that when setting it up or if it stops working, they first need to call their brother-in-law or nephew again... and for exactly those, LAN sockets for the real devices that can actually use high speed are extremely useful. Plug in, works. Unplug, doesn’t work anymore. Everyone understands that.

The rest can then be done by WLAN optimized for 95% of cases. For the effort you put into a 99.x% solution (hundreds of hours and euros), they put you into the freak corner or just give you the finger.

So just move yourself from the ego perspective to the bird’s eye view ;o) and you will understand that what you describe may by far not apply to all builders.

Thank you, I also think that as a "normal person" you don't have to overdo it. I will plan one access point on the ground floor (in the middle of the dining/living room), as well as one access point each in the hallway on the upper floor and attic. They will then transmit signals through a double-layered drywall wall at most, nothing more. Otherwise, I am equipped with LAN in the living and sleeping rooms. If the APs don't work, I can still retrofit at these locations.

Thanks again for the valuable input

No, you don't need a Cloudkey.
You can set up the APs as standalone or install the controller software on your computer. As soon as the controller is offline, some functions like VLANs no longer work and there is no monitoring of your network.
If you have a NAS (Synology or Qnap), you can also install the controller there. Since this usually runs 24/7, the controller is always online.
The Cloudkey is a small computer on which the controller software runs. It uses little power and if you want to use some functions, the controller should always be online. Good if you don't run Docker or a virtual machine.

VLANs do also work without a controller in the network, once set up, right?

Have to disappoint you. You are completely wrong with your assumption. I have nothing to do with the IT sector. I wrote that 5GHz does not help in the bathroom and is more useful in the living room. 3 are not half a dozen to me either. For two floors, two APs are enough. This is not extra effort but a matter of positioning. What I described is an optimized and easy-to-administer network. There are also good instructions. Once set up, usually nothing is changed anymore. described it excellently. If someone is thinking about Unifi, they are no longer in the absolute consumer range. Whoever does not want to deal with it and has nobody in the family to take care of it should put a FritzBox in the middle of the house or get an LTE Cube... (Warning irony) But whoever invests more money should not ruin the advantages through positioning. Good decision. In the dining/living room, you then have fast network. In the areas that are not that important, you still have coverage. In the upper floor and attic, you have good coverage and, depending on distance and obstacles, more or less fast WiFi. With that, you are optimally prepared and, as you rightly recognized, expandable through LAN sockets. As described earlier with the question about Cloudkey, some Unifi APs can also be set up standalone. Load app on phone or tablet. Open, scan QR on access point, and make settings. You have to do this for all APs. I don't know offhand if copying settings is possible. Some functions and central administration then do not work. But since you are more of a simple user, this is probably not necessary. You have a switch anyway for your LAN. For the APs, you use the POE injectors from the APs.

Guest rules definitely only work with a controller. I cannot tell you whether a USG (router) maintains the VLANs when the controller is offline. In general, I would always try to keep a controller running.