You can get there by bus or van. Bus would be a longer trip than if you take the van. Van will get you there in 4 hours or less.
Thanks to Darith and Ratana, they gave me phone numbers which are some of the van companies that will get you to Aranyaprathet (Poipet) border. They all speak Thai, and can hardly understand English, so better find a Thai who can translate for you before you call these numbers:
+66812863911
+66864045049
+66804532629
Experience tells me that the drivers have their own mobile phones, and when you start calling, you will be faced with a situation of having to negotiate with the driver. They keep saying "YES" and you will be disappointed to know that they did not understand your instructions at all.
To avoid confusion, make sure you jot down important things to ask the driver:
- rate per seat;
- day and date of departure;
- expected time of departure from Bangkok;
- expected time of arrival in Poipet;
- location where you would like to be picked up.
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