You can spend $30 or $300. What you can't skip is repeater capability - a radio that can transmit 5 MHz above where it listens and send a tone. Bubble-pack FRS radios can't, and that's the wall you'd hit on day two.
Handheld first
Start with a 5 W handheld. It's what you'll carry, what you'll learn on, and what you'll hand to a family member. Things to look for on the box or listing:
- "Part 95E certified" or "GMRS". This matters legally - the FCC requires GMRS radios to be certified for the service. Radios sold as "ham" or "Part 90" (the ubiquitous UV-5R family) are technically not certified for GMRS even though they can be programmed for it.
- Repeater channels (often labelled 15R-22R or RPT15-RPT22) and split tones - a different tone on transmit and receive.
- A removable antenna (SMA connector). The stock rubber duck is fine to start; a better one is the single biggest upgrade you'll make.
- Programming by cable or app. Programming 22 channels through a keypad gets old.
Popular, well-regarded starters at the time of writing: the Baofeng UV-5G / GM-15 Pro, the Wouxun KG-805G, and the Midland GXT series if you want something a kid can't reprogram. Ask in your state's GMRS group - what's good changes every year and people there own them.
Mobile later
A 20-50 W mobile in the truck with a proper antenna on the roof is a different world. The Midland MXT500 and Wouxun KG-1000G are the common answers. Wait until you know which repeaters you actually use.
Why watts aren't the point
Going from 5 W to 50 W is a 10 dB gain. Going from a handheld's stock antenna at chest height to a quarter-wave on a car roof is easily that much, and it improves receive too - power only helps you talk. Height beats power, antenna beats height.
If you can only buy one accessory: a decent antenna. If you can buy two: a programming cable.