I provided 6-months+ for mine (Hanoi, SP). Someone else I know (Hanoi, SP as well) only provided 3 months and also got approved.

No.

Participant(e) anonyme you'd need to ask them, I really don't know.

House of Taste Thai Cooking, in Bangkok. Got my DTV in 3 days (Hanoi embassy) through them. 6-month course.

Lol, those people trolling about other people's CHOICE to use an agent... I did, I'm not commenting anonymously here, and I'm GLAD I used a professional agent to optimize my own application, which I got in 3 days. I've seen so many posts of people getting their application refused, since mid-2024, that the extra USD200 that I paid for the service were nothing compared to the peace of mind and the satisfaction of being approved in one shot and so quickly. To each their own.

Participant(e) anonyme a reputable agent that you pay once will usually guarantee you approval for your visa, and they will proceed everything for you until you get approved. You just pay their fee once, and even if your application is not successful the first time they submit it, they just optimize it and submit it again, until you get approved. But you pay the visa and agent fees just once, even if it takes more than one shot to get your DTV.

Participant(e) anonyme you don't have to use an agent if you don't want to. For me, I just wanted guaranteed approval, which would have been harder to get without one, due to an extended time in Thailand under numerous visas. For a few extra thousand bahts only, I'm really glad I used one.

Participant(e) anonyme through my agent, yes.

Can. But stay in Vietnam.