Thirding on the robot. Mine is connected to Home Assistant (that’s another rabbit hole to jump in) and it cleans the whole flat whenever nobody is at home. Basically every day at least once and we never get annoyed by it’s sound.

You could try using bindfs to spoof the original user id and then chown the whole drive after successfull mounting (i’m a noob, just my understanding of the issue, don’t know if that’s really possible)

The good thing about Linux is, it’s not very ressouce demanding. If you pick the xfce version of Mint, you can get away with 4GB of RAM. But you won’t have that much fun coding as soon as you start something more ressource heavy (big data sets, ML, …) so this depends a little in which direction you want to go. However see if you can find something used, preferably something you can open from the back side to upgrade components like SSD and RAM (cheaper than buying higher specs)