I’ve been using nextcloud apps since setting up a home server, Deck has been pretty useful for me for compartmentalizing my work tasks. There are a lot of different apps you can set up, including a workspace clone, but none of them I would say are worth it unless you want to use nextcloud in the first place. There are ways to sync nextcloud with Google drive, but I haven’t tried it yet. If you have a raspberry pi you can install nextcloud using the nextcloud pi install script pretty easily. I ran it on a pi 4 without any issues for a few weeks before migrating it to an old nuc.

No, 4kwh is about the daily amount of sun hitting 1 square meter. Solar panels can capture about 20% of that