Vientiane, Pakse and Don Det: what order?

The cheapest sensible order is Pakse → Don Det → Vientiane — €33 of transport and 0.9 days spent moving.

Pakse → Don Det → Vientiane

• Pakse → Don Det Bus 3h €7
• Don Det → Vientiane Bus + Bus · overnight 13h €26

You fly into PKZ and home from VTE — an open-jaw ticket, usually cheaper than doubling back.