Yes, a Chromebook can work with local files. So can the Android Office apps. However, I'm pretty certain those apps require an Office 365 subscription on anything with a screen bigger than 8 inch, or to use certain features when editing. I haven't used them on a Chromebook, so I can't advise about the experience there.
I've used a Chromebook a little, and while ChromeOS is OK I'd personally favour a proper Linux distro. The advantage it has as opposed to normal distros is no admin stuff and it just works – but it still has the biggest problem, namely that it's not Windows. It's different again to anything else I've used, which includes Window, macOS, and a few proper Linux desktop environments. The most restrictive aspect for me is that normally you are stuck with either the web browser, the (few) built-in apps, or use Android apps (which doesn't seem "right", and aren't necessarily designed for it). Oh, and right-click by holding down Alt while clicking, although that may be hardware-dependent.
The other thing is, most of the cheap Chromebooks have pretty low-end hardware, including storage, and probably no upgrades possible.
My guess is that a Chromebook would work OK, but I'd probably look at a proper laptop. In that price range you should be able to find something pretty reasonable.
Recommended Power Supplies Recommended review sites Why stores shouldn't be removed RAM voltage
i5 7400, Gigabyte GA-B250M-D3H, 16 GB DDR4, integrated graphics, Adata XPG SX8200 480 GB (NVMe), 3x Kingston SSDNow KC380 120 GB, Corsair MX100 128 GB, Spinpoint F3 1TB HDD, DVD writer, all inside a wood case I built, Dell U2412M 24", U2311H 23" IPS and Philips 150B4 15" monitors, wood-bodied mouse, Dvorak keyboard, openSUSE Tumbleweed, Windows 8.1 Pro in a VB VM inside Linux
I may occasionally give advice regarding (consumer) law, but it is only my opinion based on my reading – I am not a lawyer.
Romans 3:23; 6:23; 5:8; 10:9-10,13