Used might be an option, but I always worry about buying used tech since they are built with planned obsolescence. How long until things start failing, and the replacement costs add up to what you would have paid to buy a newer model? Not saying that this WILL happen, but the likelihood is too high for my comfort level. My current laptop still works, but one of the reasons I want to find a replacement is because I’m getting very nervous that it’s going to fail soon.
Looking around, it definitely still seems that Chromebook conversion is the best way to go at the sub $500 price point. It seems that the Asus Chromebook Flip will have all the most necessary specs, including touchscreen for local edits: http://m.thewirecutter.com/reviews/best-chromebook/. It’s already reasonably well supported by the GalliumOS kernel, except for internal audio, which is nearing support: Skylake Platform Validation · Issue #274 · GalliumOS/galliumos-distro · GitHub. Actually, there is way more hardware support for this model at this stage than there was for my C720 when I first bought it. I’ll probably wait until the holidays to see if there are any good sales, but I think this is the one I’ll go with. Thanks for all the input!