Nobody seems to have answered the CB radio question so let me help because it's my specialist subject and I used it in the UK.

The range is pretty much limited to line of sight. At 27 MHz I managed to transmit 50 miles from a hilltop but both I and the person responding were using "burners" giving around 75 Watts, and a decent antenna.

The antenna is key. Unless you are using an efficient one, nothing else matters.

I used a "burner" rated at 100 Watts output with 4 watts input (FM). However, I ran it with only 3 Watts input because otherwise the "splatter" (unwanted interference) was tremendous. The difference in range between 75 and 100 Watts wasn't noticeable. Obviously, if you are simply listening, the transmission power is irrelevant.

Realistically, on flat ground, 4 Watts of transmission power will provide a usable range of around 5 - 10 miles with a decent antenna at roof height. Terrain will affect this. You get reflections off hills and buildings, which might help or hinder.

As I didn't want trouble from neighbours, I made my own antenna from an aluminium mast with an ordinary TV antenna on top to form a "capacitance hat". The mast was insulated from its support bracket and the ground-plane was made of wires inside the roof space. I used specific lengths of 50 and 75 Ohm coaxial cable to provide impedance matching.

The range can be increased slightly by using single sideband transmission. It was also more private because not many people used it. When I was in the UK, this was illegal but, provided that you didn't cause interference, and stayed away from the amateur bands, nobody was likely to bother you.

I don't know anything about the current CB scene in the UK or USA but I suspect that it's a lot quieter than it used to be.