Travelling Laos is quite easy, people are relaxed and friendly. 30-day “Visa upon Arrival” at International borders for 30 US$, home vehicle documents, Carnet de Passage not accepted. Instead you pay between 2,50 – 8 US$ for a Laos vehicle Import/Export-document, valid 30 days. If you want to extend contact customs in Vientiane. At smaller borders the Im/Ex-document is not even asked for. The total entry/exit process requires not more than 30 minutes at the border and another 30 min at customs, no inspection, no need for Lao driving license nor car insurance, just relaxed friendly people.
Lao road conditions far better than expected but quite narrow and curvy in the North, potholes may come unexpectedly, we made 40 km/h on the average in Northern Laos, 70 in Central and South because roads are flat. Beware of driving at night or off-road, still 2nd Indochina War mines. Anyway better to drive slowly and to adapt to situation-, not rule-oriented behavior: Right of way means nothing, wise drivers offer it to mopeds, pedestrians, chicken and minor roads. Diesel more expensive, 70 Euro cents/l. Toll on some bridges and roads, reasonable entrance fees.
Especcially in Vientiane try to avoid policemen just stopping you coming in sight. Bribes between 5 and 10 US$ for, say, lunch aid. Bribing no problem on the countryside and police controls are quite rare there.