You need to look at EVERYTHING! And even then you may still get burned. You can get some very good equipment and deals on eBay but it takes time and research what you are buying FIRST before spending your money.
I was looking at what was advertised as a TK-3170 UHF radio. Some of the photos looked like they were lifted from the manufactures web site, had that "new" look, not what you expect from a "used" radio. Others showed obvious signs of usage. One showed a partial of the rear of the radio which showed the model as a TK-2170 VHF type, which I would not mind getting anyway, so I ordered it. Well it showed up and it was a TK-3170 alright, name plate didn't match the sellers photo, but for the totally useless band spread of 400 MHz to 430 MHz. It was now obvious the seller was completely dishonest in his listing and knew it, not a common mistake where some sellers get the model or description wrong. That's why I like seeing the name plate with serial number, FCC ID and model number. The seller had a 99.8% rating too, but not after I was done with the feedback. I finally got eBay to refund the cost plus shipping.
I've purchased plenty of handheld radios off eBay, have a good collection of them, so I know what to look for but still got burned. So if you don't have experience buying used, don't, or have somebody who does look it over and do your research.
Well, I don't think anybody really knows what to look for at first, but you usually get decent at it after a couple of purchases, especially if you get burned early. Also, keep in mind that If price is too low sometimes is not indicative of a dead/bad radio either, as I've purchased a couple of VHF 6550 for 60 bucks, in mint condition... with charger... it depends on a lot of factors.
One thing is for sure, most Motorola XPR radios will be in fairly decent condition electronically, even though the housing might be all beat up... also those radios are meant to be repaired too, and replacing housings, etc, on Moto radios is actually easy... and there are videos on YT that explain how to do it, etc. I don't know much about other brands besides Vertex and Moto...
I have now an extensive collection of second hand Motorola XPR7550e radios now, a couple of them have a slightly scratched display, but that doesn't affect how the radios work... nothing cheap comes even close to the level of performance you get out of those radios.
Using the gun analogy, you buy quality guns, not something that might fail, jam, or stop working when you might need it the most. Here is basically the same, if you want a good radio for GMRS and potentially ham, I think the XPR7550 is probably the radio to get. And if you have money, an APX multiband is probably a better choice, but you're talking more $$$.