by car and train into Lao at Nong Khai

I will be traveling to Lao with a friend by his car. However in Nong Khai I'm going to take the train, he crosses by car, and we re-unite at the Thanaleng/Dongposy railway station to continue.

Would people who have done this border crossing recently recommend to get a visa in the Lao embassy in Bangkok (where we are now) or visa on arrival? I remember the visa on arrival from 2011 and 2014, it was pure chaos! Is there still a significant price difference for paying in THB or USD?

Car crossing has been covered here:

https://www.thaivisa.com/forum/topic/1073697-driving-to-lao-on-thai-dl-idp-not-needed/

Car insureance compulsury or recommended? Where best to get?

" By the way, Tokyo Insurance right next to Lao immigration at the bridge crossing is your best bet for Lao vehicle Insurance. "

from above link

Visa rule changes for Lao were announced for late 2018 or early 2019, has any of this come through? We are from Germany and Spain and will cross on 12jan2019.

Taking the car in at Nong Khai / Vientiane and return in Pakse to Ubon should be no problem?

Exchange money here in Bangkok or better in Vientiane (where exactly best rates for EUR or THB)?