I went there for my Ed Visa. It is simple and straight forward.
One thing that was stated on a sign there and on my queue paper was, "You must have an address in Thailand " It would be a good idea to be prepared for it.
There is a hotel across the street from the Thai Consulate called Douangpraseuth Hotel located on Rue Bourichane Rd.
Not the cleanest place but low budget and great location.
I just received an ED Visa from there 2 months ago. My paperwork also said a criminal background check was required, but the school told me that didn't apply to Americans, and I didn't need one.
Nothing was said about it in Vientiane and I received my visa no problems.
I just received a visa from there 2 weeks ago. There are signs up that say, "Please dress respectfully." Many people were there in shorts and tank tops.
There are also notices that say, "You must have an actual street address in Thailand. "
I saw a sign that said that, and a paper with my queue number said that.
Having your paperwork in order is more important, but don't go looking like you crawled out of the sewer either.
I went on a Tuesday at 7:45 and was number 54 in line. There is a hotel right across the street from it. Not the cleanest hotel but a very short walk to the Thai Consulate.
The paperwork I got from the Thai language school says, "Please note that if the applicant leaves Thailand they will need to apply for a re-entry permit from immigration to avoid invalidating the Ed Visa and re starting the process." (The process of applying for a Ed Visa)