Hello,
I would like to use Nextcloud to store files, sync them and share them with some friends.
I’m thinking to use a SBC like a RockPro64 and NextcloudPi. The files will be stored on an external HDD.
I’m wondering about the place needed to install NextcloudPi: I was thinking installing it on a eMMC or SD card to separate the system from the file storage but I cannot find which card size I will need to buy to host the OS. 16 Gb? 32 Gb? Other?
Maybe I can’t find this information because my whole setup idea is wrong… In this case I would really appreciate some general advice on this topic! 
Thanks!