A 48V rail would make more sense. Just like USB-C did to get 240W power delivery over a small cable.

Thanks, I’ve seen a few but they seem more expensive than the WiFi equivalents, I’ll look into some more

Posteo.de if you don’t need a custom domain, Mailbox.org if you do.

For cloud storage it should be a different service anyways, it’s best not to combine things with the same company. So for example Tresorit for storage, Bitwarden for passwords, Mullvad for a VPN, etc…

Do you know roughly how much range they can get? I have wifi sensors out like 500 feet from my house that work OK, but in my research on Zigbee most people say like 100 feet or less?

Maybe Karadav with the Nextcloud clients/apps.

Not sure if that will support selective sync, I don’t see anything saying specifically no on the repo.