Do I need to make an appointment at the Thai consulate in Vientiane if I am going to apply for a non-imm B visa (volunteer) . . . .and how many nights will I need to say - ie. whats the turn around for visas there? Thanks!
TLDR : Answer Summary
You do not need an appointment at the Thai consulate in Vientiane to apply for a non-immigrant B visa for volunteer work. You can drop off your application on the first day and typically pick up the visa the next day, so plan on staying at least one night.