DataPurger. I like to save the meaningful/useful stuff, but I don’t keep everything for the sake of it. I try to have an efficient workflow during content creation, and purge the unwanted stuff straight away.

The app (google Authenticator) uses it to verify your device. You can use the saved image to authorise your new device through the app.

Save your QR codes to the notes app and lock it.

I think it’s any Apple device with private IP address enabled

The HP Z600 is good value for money. Units a few years old can be bought cheaply. They’re quiet for the compute power on offer. There are hundreds of different configurations available all the time on eBay.