Hi there, I'm interested in the most cheapest way to Hong Kong from Fuzhou.

You can take a bullet train to Shenzhem North first, which takes about 5h 30 minutes, CNY259 for a second class seat and CNY414 for a first class seat. Then take metro line 4 and get off at Futian Checkpoint from Exit B. It takes CNY4. After passing the barrier, you can enter HK to take East Rail Line at Lok Ma Chau.