Recommended approach to photo/video/file backup for multiple users on different networks

[Bimrin]

Trying to help someone setup a new qnap and one of the use cases they had was they have older parents and in-laws that they would like to give the ability to backup data (important photos, videos, documents, etc). Is there a good or even recommended way to implement something like this, all the people accessing live in different locations so not a single network. I am so used to keeping my qnap locked down inside my network I haven't really played in this space at all.

[dolbyman]

If you have full control over the network equipment you can do several site to site VPN's that will establish the connection to offload the data to that central location.

Honestly though, it's probably cheaper and easier to just backup to a cloud hoster...If you then want a central copy of it on a QNAP, you can sync it down via hybridmount.
https://www.qnap.com/en/software/hybridmount

[Bimrin]

Thanks @dolbyman appreciate the sound advices as always