This isn't necessarily what you want to hear but why are you getting a Chromebook? I'm assuming it's required for your school, in which case I'd get the cheapest one you can live with
This may be obvious to some, but for everyone else:
A Chromebook is not a computer. It's a giant Android phone. Unless all your problems could be solved by a bigger screen and keyboard for your phone, do not buy a Chromebook.
C'mon, it's still a computer. It does exactly what most non-technical people need a computer to do. If all your tasks can be done in a web browser, it's even kinda good at that. I worked exclusively in ChromeOS for more than 8 years and it was a pretty Mac-ish "no fuss, just works" experience.
That said, I myself would never buy one for personal use that doesn't have Linux firmware. That will give a longer life and the other capabilities you probably have in mind.
If you are looking for a cheap small laptop with good Linux compatibility and decent specs, I certainly support your search for a chromebook to use as a platform.
However, I am typing this from a refurb Lenovo X380 which was 1200+ when new a few years back, but which I picked up for around 200 bucks a year-ish ago. I have manjaro on it, and it's flawless. Comfy keyboard, pretty good specs, great looking 1080p display.
I liked it so much I talked my mom into getting one when she was on a similar quest recently. She lives too far away for me to push her out of her comfort zone, so she's running Windows on it, but even with Win10 it's a pretty good performer for typical tasks.
I love the darn thing - apologies if I've misread your goal though.
They now have the 16GB model avail for about what I paid for the 8GB model. (And the seller I bought the 8GB model from is charging more for it than for this 16GB model, oddly)
A used one in your area, so long as it's newer (2021+)
I would recommend using Linux on it instead of ChromeOS, if you're a little more technically inclined. ChromeOS is fine but it limits you to just the Google ecosystem whereas Linux allows you to do things with it like a normal computer.
I took an old (2017?) model and put a super lightweight Linux distro on it and use it as a little administrator device. It's got good battery and acceptable processor speed, but it's severely limited by CPU cooling and storage.