On a Mac if you click [alt] while clicking the wifi symbol you get an additional option called wifi diagnostics.
If you then click [cmd] and press 4, it will scan all the wifi signals it can see and it will tell you what channels they are using, and it will be able to tell you the best...
I needed new electrics anyway. Have been using powerlines though, definitely worth hardwiring as much as you can and reducing the need for wifi, especially from provider hubs.
Wifi is the devil's work. Multiple devices and clients, the BB providers routers just cannot handle it. My VM superhub 3.0 hardwired connection is pretty consistent, the wifi is all over the place, but that can be impacted by so many things, interference, construction of the property etc. Not...