In dollars
Rough USD equivalents
Vietnam prices in VND and your card or exchange counter prices in dollars, so a rough map helps when you budget. At around 26,000 VND per US dollar, the Le Thanh car works out to roughly US$140, the Cambodia handling add-on to about US$42, and a single-entry 90-day e-visa to about US$92.
The rate moves a little week to week and your bank will quote its own. Treat these as planning numbers, not invoice numbers. The booking form always states the total in VND before you confirm.
Cash to carry on the day: US$30 to US$35 per person for the Cambodia tourist visa fee at the gate, plus small change for coffee and pho at the An Khe stop. VND is fine for everything on the Vietnamese side.
Doing it yourself, honestly
Why the DIY version rarely works from here
Public buses do run Quy Nhon to Pleiku. That is the easy half. From Pleiku you still need to cover the last stretch to the Le Thanh gate, cross, and then find a ride back to Pleiku in time for an evening bus to the coast. Miss the connection and you are looking at an overnight in Pleiku or Duc Co with a border crossing that never happened.
The gate keeps roughly 07:00 to 19:00 hours, and it sits hours from anywhere. A missed afternoon stamp means the whole trip resets tomorrow.
The per-car price exists because a driver who knows QL19 and the border routine is the difference between a long day and a very long two days. Most groups find that worth splitting three ways.