Hello,

I live in a quite big house with 2 floors and another building next to the main house. This house is old and got walls from 1 meter thick.

At the moment I have 3 wifi access points : one for the ground floor, one for the first floor and one for the other building. The last one is connected to the main house through power line (PLC) beacause it's impossible to pull an ethernet cable.

As my 3 access points are from 3 different brands, my phone always connects/disconnects, jumping from an accesspoint to another one when I walk through the house.

I'd like to setup a real wifi mesh system with same ssid and roaming. 

In the main house I'd put 3 wifi access points which would communicate through ethernet backhaul and not wirelessly because of the thick walls. Which TP-LINK units would be okay for that ? 

And in the other small building I'd need a wifi access point running through PLC. It would then look like this :

In red : ethernet wires

in purple : PLC

in yellow : wifi beam

The router will be the one from ISP and will act as main router with DHCP server and firewall.

The Deco units should work in access point then.

Will the wifi roaming work even if there are 2 switchs one after the other ?

Will I be able to get wifi without interruption through the house ?

Which models would you advice for "Deco Master" ? E4, M4, M5  ?

Which model for the 2 DECO PLC ? P9 or P7 ?

I'm a bit lost. Sorry for poor english and drawing :-)