For the cheapest, almost "disposable" radio it's hard to beat the Baofeng UV-5R[1] at $30. However they aren't the most reliable and they tend to be pretty spotty in terms of how clean they are(broadcasting on frequencies other than you're transmitting). They're also a total PITA to program, but for emergencies you can put them on 146.520(national calling frequency) and leave it there.
A little step up from that is Yaesu's FT-60R[2]. It's a lot more robust, easier to program and generally much more solid. It also costs a fair bit more($180).
I usually carry a Yaesu VX-8DR[3] however it's overkill for most people. I mostly have it because you can drop it into a few feet of water without issue and it does APRS so I can send "text" messages and see status of other APRS beacons near me. It's also pretty darn expensive at $370.
All of these will also receive FM radio, NOAA radio and any of the un-encrypted Fire/EMS/Police bands so that's handy as well.
With a handheld tranciever the best you can look for is 2-5mi depend on terrain between who's receiving you. If you've got a repeater nearby, those tend to be ~100W(as opposed to 5W HTs usually do) and positioned well. Usually they cover anywhere from 30-100mi(we've got one in Centralia that I can pick up from Portland to Seattle).
Regular radios start in the 25-100W range and get out 10-30mi depending on terrain but those are usually a lot more involved to setup. One nifty thing is most dual band radios these days will do cross-band receiving so you can put your HT on 70cm and have it retransmit via the larger radio on 2m. If you have it setup in your car that's a nice setup for a quick an dirty repeater.
[1] https://www.amazon.com/dp/B00HX03AMA
They certainly aren't a match for Yaesu/Icom/Kenwood, it's pretty well known that most transmit well above the FCC rules for interference [1] [2].
[1] https://kd8twg.net/2015/10/17/a-quick-and-unscientific-spect...
[2] https://sm6vfz.wordpress.com/2016/11/11/baofeng-uv-5r-spectr...
It would often make sense to have two units, by the way. (Oh, and by all means get a licence - it is not difficult, and it gives you opportunity to learn how to use the device before you need it...
The FT-60 can also be modified to transmit on other radio service bands (like FRS/GMRS/Marine VHF), though it is only legal to transmit on those bands with non-type-approved hardware in honest-to-god emergencies.
I always cringe at the prepper types who boast about how much they spend on their arsenal, but cheap out on radio gear. Realistically, cooperation ensures the best chance of survival. A good radio and an aftermarket whip antenna will be more useful in all situations besides the end of the world.
[1] https://www.ecfr.gov/cgi-bin/text-idx?SID=4cae37ae392f692b37...
You only need a license to transmit.