try Ho Chi Minh. Consulate there are very nice and helpful. Send them a message asking what docs they require. Prepare them, and you will be done within 10min!!! Go next day to collect passport.....2 minutes
it is, if you do it right from the beginning!! No need for any agents, if you have everything in order!!! immigration is all about submitting the documents they require!!!
you do not need an agency. Just go to the immigration office, ask what docs are required, photocopy all docs, go back to immigration and ask if all is in order.....saving 20,000baht!!!