Any suggested models? They’re a bit cryptic to me.
My oldest is a 3+ and is at least a generation before Gopro had a screen on the back. Now, I'd get one that does just to make it easier to set up. That said, my second one is 4 Session that I like, but they no longer make, because it us just a little smaller. Honestly, for how I'd like to use one, if they made one half that size, I'd consider it.
But again, the price of being smaller is that it doesn't have a screen, so you have no idea what your video looks like until you download it. If you're okay with that, you can buy them pretty cheap. If not, then stick with a newer one that has a screen on the back.
There weren't any other huge leaps in technology between generations so unless you have a very specific need, buy a cheap one, from a reputable seller, on eBay, and play with it to see how you will use it.
You might also comparison shop to get one that has more "stuff." The basic thing us the waterproof case, but after that are clamps, brackets, goosebecks, straps, headbands, and all sorts of other things to mount it to your head, body, bike, kayak, tripod, helmet, etc. There are also some ridiculously cheap packages available online that will supply you with more of that stuff than you are likely to use. I bought one and it's been occasionally handy.
