I would avoid that option if I was you. Have you ever been there, I have? It is decades behind China outside of the major cities (not sure if that is a bad or good thing, but there you go!)

You may still find you are expected to pay money to her family, as it is seen you are buying a commodity...not to mention the language may be unfathomable if you have come from China, and the bigger cities like Saigon may well be more expensive.

Heed my warning, lest you get burnt there.