To assist others, here is my experience of applying for a tourist visa in Vientiane (Laos). I booked an appointment online ([members only]/) (I recommend to do it at least a 10 days before your trip otherwise your date will not be available).
A week later, I arrived in Vientiane at the Thai embassy. Although my appointment instructed me to come around 10 am, I arrived at the opening at 9. There were fewer than 30 people, and the entire process was exceptionally fast. After waiting in line for 10 minutes, it was my turn.
Here are all the documents I provided:
- 1 copy of the main/bio page of my passport
- 1 copy of the page with the Laos stamp and visa
- The filled visa application form
- 2 ID photos attached to it (you have to glue them yourself; there was glue on the table)
- 1 copy of my flight ticket to enter Thailand
- 1 copy of my flight ticket to leave Thailand within 60 days
- 1 copy of hotel booking (I booked for just 3 days)
- 3 copies as proof of finance (3 months' billing of my bank account; they were not in English, so I underlined the amount on each page to avoid issues)
In the end, the guy checked my documents, and it took less than 30 seconds before he approved my application and gave me another appointment to pick up my passport two days later.
I applied on Wednesday morning and picked up my passport on Friday afternoon.