I read about Shanghai South Bus Station where I can supposedly take an express bus to Tunxi. So, where is this station exactly? Is the Shanghai South Bus Station the same as the Hutai Road Long-Distance Bus Station?

Other questions:
1. I am getting a friend to pre-buy the bus tickets. Can somebody tell me the exact bus number and what are the possible departure times for the express bus?

2. what is the price? Is there a special price for seniors (65 years and above)?

3. please give me the Chinese name of the bus station where my friend can go buy the bus tickets. He does not understand what I mean by Shanghai SOuth Bus Station.

4. Is it necessary to pre-buy bus tickets or is it "dangerous" to buy them on the same day of departure. I plan to leave on 28/9 to Tunxi and was told that it is near public holiday and big crowds are expected for Huangshan.

Please help urgently. Thanks!