You cannot own land, ever. Every property you "purchase" (a house, apartment, commercial lot) is actually just a 70 year lease.
There's no such thing as internet (or telecom for that matter) privacy. Every single text message, Wechat message (similar to Whatsapp or Facebook messages), phone call, search query can be retrieved and analyzed by authorities. If the police wanted to find out who you called or texted last night and what you guys talked about, they can.
There's no such thing as an Immigration bureau. Compare this to the U.S. which has the biggest and busiest such department in the world, with functions split across the DHS, INS ("Immigra").
Most small businesses find ways to dodge taxes, completely.
OK, enough of the negative, some positives:
No legal drinking age limit.
You can get food delivered to you, anywhere, any time for less than a dollar. Even in sub-15 celcius weather, in snowstorms, even when the deliveryman has to climb 10 flights of stairs to get to you. No tips needed.
About #2, no tips needed... that actually applies everywhere, for any service.
Despite the well known Internet censorship, there are places you can get on Facebook, Youtube, Google completely unhindered (without a VPN of course). These are usually select western hotel chains (it's quite random which ones get access), a few expat communities in Shekou Shenzhen, and elsewhere.
You can get the New York Times (paper version) delivered to you for free at the Park Hyatt Beijing, but you won't be able to log onto NYT.com from your hotel room.