I have a property with a separate apartment that’s used for AirBNB visitors. Obviously, I’d like their network activity to be isolated from my main network. There is only one ISP connection, and the ISP modem/router can work in bridge or router mode.

I am considering a network of 3 or 4 X50’s, and can use Ethernet backhaul between them, via a switch into the main X50, itself connected to the ISP modem.. I know I can use the guest network functionality, but I'd rather the devices on that network not be isolated from each other. That way, visitors can bring their own devices like smart speakers and TV dongles, and have them work on the guest network.

I’ve read conflicting reports as to whether the guest network isolates devices from each other or not. Can someone clear this up for me please?