I'm a long-time user of free/open source software, and write various things for both fun and profit. I don't take myself all that seriously and I do all of my own stunts.
You can find me at these fine establishments on the web: Open Source Musings, The Monday Kickoff, Weekly Musings. and The Plain Text Project.
Authored Comments
You can overwrite ChromeOS (which is what I did) or dual boot by installing using a utility called chrx. More information here: https://wiki.galliumos.org/Installing
If you're using web apps with your Chromebook (whether running ChromeOS or a lightweight Linux distro), then obviously your files will reside on whatever server they reside on. Unless you're working with large audio and video files (something a Chromebook really isn't meant for), then the amount of local storage should be enough for most purposes.
My Chromebook, for example, has a 32 GB SSD. At the moment, I have around 23 or 24 GB free. If your Chromebook has a smaller SSD (even if it doesn't), you need to be mindful of the amount and size of the software you install on it, and the number of files that you keep on the device.