I'm from the US and plan on staying with a friend

I'm flying into Beijing on a one way ticket Sydney to Beijing. I have a round trip multi city flight booked from from NYC to Sydney and Beijing to NYC. Does it make a difference that they're not booked together? Once, in Beijing I would like to stay with a friend, who will be there to pick me up at the airport. He's staying on a US visa and just moved there recently. When checking in at the Police Station with us. What information (ID cards, passport, etc.) will he need to provide? Thank you!