"Client Isolation" just isolates wireless computers from each other.
8840T will still work as the main router, right?
TD-W8970 has guest network function. Clients connected to guest Wi-Fi will not be able to communicate with other clients. Is it proper for you?

Hi.

Thank you very much for your response.

I should have been clearer in my initial post. If i buy the w8970 there's no point of me having the 8840t, since they do exactly the same.

I would like to avoid turning the guest mode on since i want just one Ssid active, unless i can just have the guest mode on. Is this possible?

My main objective would be 8840t and a N300 Tp-link wireless router since is cheaper this way. I don't need any wireless devices to connect to the computer on 8840t. Isn't there a way to have something similar to guest mode by using this setup?

Is it possible to block access to my computer (8840t) by setting a rule in the wireless router firewall or this is impossible?

Thank you once more.