Hi, I got my tourist visa from Vientiane and I would like to share my experience that might help some people.
I exchanged money in Nong khai and rate was 1 Baht = 550 Lak. Also exchanged in Vientiane (std exchange ) 1 Baht = 650 Lak.
I got Laos e visa and it was 1900 baht. People who get visa on arrival pay only 1000 baht (that's what they told me) and all process same, there is no any advantage of having e visa. I will be happy if someone correct me or shed some light .
Rent a motorbike from Elephant Motorbike for 250 baht per day.
There is a bus from vientiena bus station to nong khai bus station and it is just 15.000 Lak.
Immigration process is smooth as long as you have all documents.