Thanks to everyone for ideas and your time. We have set a dropbox account and sent out a file request link, it is filling up already.
When this anniversary is over, on our next meeting I will bring up the possibility of deploying our own NAS with nextcloud at our building.
Cheers

I know of it but haven’t tried it yet. For my personal needs I actually use Zerotier to connect to my server remotely, but having two IP adresses is a bit anoying and not family friendly. Also it doesn’t work 100% of the time, sometimes I have troubles connecting. When the right time comes and I will get my IPv6 address I will switch to Wireguard to tunnel home, but until then…
In my case right now, any VPN is out of question, as it doesn’t meet the no-authorization condition, and I don’t want 60 people poking around on my LAN.
But thanks anyway, I might try Tailscape over zerotier to see if it is better.

I do run Nextcloud on my home server, and in an ideal world I would like to use it as I have sufficient disk space, even though my internet connection speet would be the bottleneck. The problem is, I am at the moment hidden behind a hell of a NAT maze and my server is simply not accessible from outside, even with VPN.
I have found out in the meantime, As you said, I found out as well, Nextcloud permit uploading without need for signing up. I am now thinking about setting up an acount at some Nextcloud provider, but they seem to by limited by capacity…

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