Video doorbell system with two-wire, new construction

Hello everyone,

our single-family house is about to be completed.

Now it is, among other things, about which doorbell system should be installed.

We were a bit naive/not up to date and just thought of an intercom system, possibly with a camera, when planning.

After I initially got a little idea of what is possible nowadays (among other things, I like the possibility that you can be notified via your phone when someone rings the bell even when you are on the go and can talk to the person), I briefly asked our electrician about it shortly before/during the installation work. Unfortunately, he has zero knowledge of modern doorbell technology and therefore could not/would not advise us. Back then I had read something about WLAN-capable systems and thought, okay, maybe we’ll do it that way. I also didn’t have a clear mind to look into it more deeply.

Now the topic has come up again because it is becoming urgent. And I promptly read that for a new build you should have LAN installed and that a WLAN solution is only for retrofit. We only have two-wire here. I am very frustrated that the electrician made no effort to deal with it and advise us (we can’t be his first customers interested in this, right?).

And when I then read something like the following in a post from 2021, my frustration with the electrician is even greater:

It is simply very old technology and no longer state of the art today. Two-wire is actually only used when you have to retrofit in existing buildings and only have a classic doorbell wire. It is always a compromise compared to "real" LAN. Conclusion: You simply don’t do it anymore today and it is absolutely not recommended if you have to pull cables anyway.

There are also huge differences between "transmitting video" and "transmitting video." I assume you want to see "who" is at the door and not just "whether" someone is at the door.

Now my questions, and please excuse me if they are totally silly, but I am overwhelmed by the information and offers:
Is there also the possibility with two-wire to offer such a solution as I described above?
If yes, in what respects would it be worse compared to LAN (image quality)?
Or can we still do something meaningful/retrofit with the home technology?
For LAN, the floor would have to be opened again, as the house is already quite far along.
What disadvantages do I have because there is no LAN now?
We have two levels (entrance and living area upstairs, bedrooms downstairs), and on the lower level a normal intercom system is planned so far. Does anything have to be considered for that?

I am so at a loss because of the abundance of information and don’t know what to sort through or discard.
Thank you very much in advance for your help!

Is there also a possibility with two-wire to offer a solution like the one I described above?

Yes, there is. You can also do PoE (LAN with power) over 2-wire. Some offer that, I have had multiple good experiences with 2N (Verso IP or recently the Verso 2.0 with better camera). There are definitely adapters with LAN > 2-W > LAN, which are simply called "2Wire" by 2N. That is basically no different from Powerline (e.g. from Devolo) with slightly fewer disadvantages. But it works.

If yes, in what aspects would that be worse compared to LAN (picture quality)?

Not at all. We’re not transmitting 4K here and well under 100 Mbit is enough for HD. There are just more devices in between (converters from LAN to 2-wire and back) and you have a media conversion. Otherwise, you can do it and it’s better than WLAN as well. But make sure you really get a system with LAN over 2-wire and not a "real" 2-wire intercom. THERE the quality is then garbage.

Think about what you want beforehand.
Ring the gate with video, speak, hear, open with door buzzer,
Ring the front door with video,
Inside the house downstairs and upstairs all of that too,
And maybe all of that also from the phone

We only have two-wire here.

Really set firmly in plaster or laid properly in a conduit as it should be?

Really embedded in plaster or installed in the conduit as it should be?

I think in the conduit.
But I already asked if it would be possible to pull a LAN cable through the conduit (if that's what you meant with your question), and he responded very hesitantly/unwillingly and said something would need to be chiseled open.‍
If you have any comments or tips on this, I could ask more targeted questions (then I would know exactly what to ask for).

Think about what you want beforehand. Ring the doorbell at the gate with video, talk, listen, open with door buzzer, Ring the doorbell at the front door with video, All that downstairs and upstairs inside the house as well, And maybe all that also from the mobile phone

All of the above seems interesting to me. For example, that you can also check who is ringing from the garden via the mobile phone (and possibly even open the door then).