Sending ID for WG contract as a non-EU resident

Hi everyone,

My friend just got an offer for a WG flat in a city in Germany, and they asked him to send a copy of his ID so they can create the contract. He is new in Germany and not sure if he should blur some details or send it as is.

Also, what exactly do landlords need from the ID, and which ID is best to send as a non-EU resident?

Thanks in advance for your help!