CheyneBC wrote:Also, how do I determine which visa is better suited to my intended length of stay?
Business or tourist?
You have already stated in another post that you are coming here as a tourist.
You won't be eligible for a business visa without a stated intent to explore business opportunities, or if you are going to be employed here.
You also asked elsewhere about a "residence visa".
You won't qualify for that as a tourist unless you marry a Vietnamese man.
You also asked about how to trust a particular agency.
You don't necessarily need to go through an agency to get a tourist visa.
The Embassy or Consulate of Vietnam in your country is your first best option.
If you find yourself in a situation where you need the assistance of a Visa agent, it's best to ask someone whom you trust to recommend a trustworthy agency.