not quite sure what you mean by a visa approval, but there's almost never any need to leave the country to get a new visa.

It's perfectly possible to get a B3 visa having entered as a tourist, though.

Your best bet is to shop around the old quarter travel agents for who can get you the best price - it varies according to your nationality and their contacts.

Visa approval is that one person/org in Vietnam has to "invite" you to get business visa. But if you buy business visa through a travel agent they normally set their company name as the sponsor. I was thinking of getting business visa without going to a travel agency. Their prices are so sky-high that its cheaper to take the bus to Vientiane and back to get a visa at the Vietnamese embassy there.

Are the prices for visas "so sky-high"?

Last time I got renewal it was $87 for a six month multiple entry visa. I think the first one is more expensive than a renewal - $95 if memory serves me correctly. This was in HCMC though...

But, like grubby said, the price varies from agent to agent. The visa costs $50, and the stamp $10 according to the details in the passport, the additional costs will be what is added for 'additional costs' and the agent's cut.

Agreed -- don't leave the country, just find a travel agent. We found Tropical Tours at 10B Luong Ngoc Quyen St. (in the Old Quarter) to be particularly good. They were able to get us a business visa when no one else could (as Americans who had extended our initial tourist visas, it was apparently asking quite a lot to switch to a business visa). Plus, they seem to offer some of the cheaper rates in town for the 6 month, multiple entry visa. Here's their website and telephone:

www.tropicaltours.com.vn

tel: 84-4-9261580