I plan to go from Hangzhou to Suzhou, Nanjing and back to the departing city by the fast train.

Per your website,

1) For HZ, I can take train G7564/G7565I (depart 8.35am) or G7572/G7573 (depart 10.04am) from East Station. I will arrive on 14th March and leave for Suzhou on 18th March.Where can I buy the train ticket near Holiday Inn CBD ?
2) From Suzhou, I will arrive on 18th March and leave for Nanjng on 21st March. Can I buy train ticket from HZ so that I am sure of getting a train ticket?
3) From Nanjing to get back on 24th March , can I also buy my train ticket in HZ?

Thank You