ISSA Compass all the way, like others mentioned as well. It's extremely affordable service and professional people. They also guarantee you success (at least when I used their service).
Not sure what agent you contacted, but you should try Issa Compass instead. They allowed hundreds to get their DTV easily, quickly, and for a very affordable fee.
Why would you want to do it yourself, risk being rejected and pay for a second or even a third application when an agent guarantees you success in one shot and in just a few days for merely a few thousand baht?
Glad you got approved! I used their service but went for the Thai Cooking School instead, and got approved in just a few days as well. Enjoy your time in the Land of Smiles :)
not just might but will. I booked 2 weeks in Hanoi for my DTV to be processed. It took a few days only to get approved, but in case of an interview or if requested more documents, could easily take up to 10 days.