Hi, I’d like to get some advice on which handset to get and which frequency to use to be able to contact my daughter in a shtf situation. We’d be communicating up to 15 miles, between semi rural and city locations. I’m looking for something simple that she can keep in her get home back, preferably runs on something like AA batteries, unless the battery pack has a decent lifespan if unused, or can be recharged by a USB power bank / hand crank / solar charger.