That's a good idea.
" walkie-talkies with ranges from 15 to 35 miles " I had no idea that walkie-talkies had that large a range. They used to sell them at Costco but the ranges were measured in feet or yards, not miles.
FRS and GMRS radios have a range of a few to tens of miles, on open land, much less than that urban or hilly areas. Shortwave ham radios, on the other hand, can reach hundreds or thousands of miles with ease, since they use frequencies that reflect off the ionosphere and back down to Earth far away. Not mentioning ham radio is, as I’ve already pointed out above, a serious omission.
They just keep getting better and better. A few suggestions about their use.
The first is that extra batteries are good, but it is also a great idea, for several reasons, to have a DC to AC converter, so you can charge your walkie talkies from your car’s cigarette lighter socket.
The second is that when you use walkie talkies, if there is interference, using alpha-numeric code is a big help. But take it a step further. Use a simple, one use code, which will defeat most of the snoops out there.