Hi, I am looking to get from Vinh Long to Ha Tien by bus - what would be the easiest way to do it?
Best way is to get a bus, moto, or taxi to Can Tho bus station, and then get the Ha Tien bus there. Journey time from Can Tho to Ha Tien is between 5 and 6 hours.
For transport to Kampot then I would recommend that you contact OASISBAR who would be able to meet you at the bus station and transport you to Kampot. Google Oasis Bar, Ha Tien for more info or search TA for Oasis Bar. Travel time to Kampot is 1h30m from Ha Tien but depends how busy the border is.
The Ha Tien border is only open from 06h00 to 18h00.
For details, requirements, and visa cost please see my post regarding Prek Chak border.
If your budget is ok, do a private transfer (You can stop somewhere on the way).
Private transfer would be between 2 and 3 million VND or equivalent in USD.