I paid 700,000 Vietnamese dong which is close to 25$ wheee they have. Night sleeper bus this buses which depart at 6 pm and they have one stop 10 pm for dinner which you have to pay around 50,000 meal with rice and some hard boiled meat
When in the morning we arrived at 2 pm that’s was a very long trip like 21 hours and I sleep just little time when I wake up at the morning at the border of cau treo which has very chaotic all, I remember it was 11 pm somewhere we stop at the border and the bus stay their until 6 or 7 am when all the buses unloading passengers for border checking . All the Vietnamese from different bus station gathered all their passport in one and there are massive Vietnamese which makes it like a market try to wait for their names to be called for the exit , I feel lucky because I handed my passport quickly and my name was called . If you are US or Canada u have to pay 40$ for the visa and less if your European national . For me as an ASEAN passport I don’t have to pay anything for the visa however they imposes 1 $ for every enter and exit pass for every nationality .