I've been lucky with RF so far.
My city residence is small so everything is close by.
Most devices are in the 2 ghz range so the issue is finding free space that has the least amount of activity.
I've recently started to add Wi-Fi devices to my off grid place and now have several old Wi-Fi enabled laptops.
I have no issue with these in the country as closest neighbor is out of range.
However in the city these are slow (even though I have cable internet)
using windows and looking for available networks I found over 10 routers online at any given time.
(And I'm in a detached House)
I know a router can interfere with x10 RF reception (the old forum is full of posts proving that.
enter inSSIDer for home
this will help you find which channel has the least traffic.
The tool works for both 2 GHz as well as 5 GHz.
this by no means will help with other RF signals but is a start.
However they do have other software tools which I have yet to test.
The office version will do a bit more but it isn't free.