The night bus from Phitsanulok to Khon Kaen Thailand left late at about 22:00 and arrived at about 03:15 in the morning. Luckily there was a quick connection to a night bus to Nong Khai and I only had to wait about 15 minutes. I slept pretty well next to a warm and chubby Thai lady. I had to put the armrest down so she wouldn't encroach so much on my seat. When the armrests are up, the big people tend to naturally expand into both seats.
We arrived at Nong Khai at about 06:30. There were a few other tourists on the bus. I thought about trying to share a tuk-tuk but it was only 100 baht for the trip to the Friendship Bridge.
At the border crossing, there was some confusion by the backpackers as to whether or not we needed photos for the Laos visa on arrival. I already had some old ones so I went on through. It turned out that photos aren't needed because they take photos of everyone.
The Thai exit was easy and there was a 20 baht bus to shuttle people across the bridge because walking is not allowed.
The Laos visa on arrival required several similar forms to be filled out and a payment of 1500 baht or 35 USD. There were quite a few people going through but no lines since they just took a quick photo and then took the money, passports, and papers and processed them inside the office while we waited in a group for our stamped passports to come out.
Outside of immigration I found the only money exchange place that was open at 08:00 and changed all of my Thai Baht to Lao Kip. Then I took a truck taxi to the center for 40000 Kip directly to the AV hotel. I didn't have a reservation because I didn't think that I would make it this far in one day and one night.
The hotel had rooms that were ready so I got right in and also had the excellent buffet breakfast for an additional charge. I took the biggest room since I had money left over for the month. It was massive with a balcony and a seating area with leather couches.
In the evening, I walked down to the Mekong River promenade park. It was nice but the actual river was a long way away. In monsoon season it is probably a lot closer. There is a big night market and many open air bars and restaurants along the promenade.