I recently had my laptop repaired (broken power/IO board) and I forgot to give the repair guy my passwords. One to un-encrypt the disk and the other my user password. Now I got back my laptop and all good except Mint (Linux) appears to be reinstalled (?). I say that because a number of settings have been reset to defaults. For example, access to the /dev/ttyUSB0 (to use a USB serial adapter you have to set permissions after a reinstall). Also, the macro setting in LibreOffice had been reset (actually all the macros were gone!), and I had to reinstall some graphics libraries for compiling some of my programs. I also "think" there are some missing software icons on the desktop (but I am not sure).
So am I paranoid or not?