@jopemedina 

This setup will work.

One of your Deco will be Main Deco, the one you configured first. It must be Ethernet wired to the router, so it'll be one of three that have Ethernet link to the switch. Any one.

You will need to configure how Satellite Deco connect to each other, the feature is called "preferred signal source," described here: How to select a preferred signal source on the Deco App

Not every Deco model offers that feature, so you have to be careful which you choose. If you wish, I may be able to help if you tell me which Deco models you consider. If you are not sure, tell me if you want Deco that supports just WiFi5, or also WiFi6, or even WiFi 6E. If you are not sure, just tell me what is the speed of your Internet connection and I may be able to help you with selection.

Once again, with your setup having "preferred signal source" feature is a must.

  @Alexandre. 

Thanks so much for your help.

I didn't know you about the preferred signal source. I have a 600mpb symmetrical Internet connection. My main working station is wired, so transferring big chunks of data through Wi-Fi is not a big deal for me.

I was considering the Decos P9 for its integrated PCL feature, but I don't know whether the P9s support this feature or not. I am also considering the Decos X55. Apparently, this Wi-Fi 6 model supports the preferred signal source. None too sure about this either.

Roughly, this is my house layout, and the strategy I'm planning:

As far as I know, I think I can set up as many decos as needed provided that they are wired. As for wireless units, I have to be more careful. It seems that more does not necessarily mean better.

I am still trying to understand the need for a main deco when all units are in AP mode. It seems it simply works that way.

Q1. Let's assume, for example, I set up the living-room deco as the main unit in AP mode. If I set up the office deco afterwards... will the main deco detect this office unit since they are connected to the same switch?

Q2. If so, would you set up the wired units first and then the wireless ones?

Thanks so much

Joaquín

  @jopemedina 

Thanks so much for your help. I haven't bought any mesh system yet. Glad I posted here before jumping in.

Which Decos are compatible with "preferred signal source"? This is something which should be easily found on the Internet, but I'm struggling with it.

Thanks

jopemedina wrote

Which Decos are compatible with "preferred signal source"? This is something which should be easily found on the Internet, but I'm struggling with it.

 

  @jopemedina 

You are not the only one. Unfortunately, TP-Link does not support consistent list of features for all of their huge list of Deco models, and also they don't provide comprehensive feature list.

Deco X55 most likely has "preferred signal source," according to this: https://community.tp-link.com/en/home/forum/topic/614754

Note that features differ not only between Deco models, but their hardware versions. For example, Deco M4 from that link only has "preferred signal source" for hardware version 4 (V4). If they sell M4 with different hardware version in your country, you won't be getting that feature.