Need to learn the lingo

Kim wrote

Hi, My name is Kim and I'm an Auzzie living in Brisbane.
I teach English online - Tesol and IELTS, and I used to speak Vietnamese
Many years ago -helping the refugees -in Melbourne.

In recent times I have decided that I really want to regain my ability to speak,hear,write and read Vietnamese.
I also have a passion for the food!

I've spent time in HCMC Vung Tau and Hanoi in the last couple of years, and I'm working hard to get on top of the language.

I have decided that it would be best for me to spend 3 months -most likely in HCMC and study full time there so I am immersed in the language and culture.
I can learn via Skype, but then the street outside my house is full of English -not Vietnamese language.
According to my research thus far, the course would cost me about $700 for 80 hours class time.and the rent in an apartment -about $150 a month.then food etc.

That is do-able -especially if I can return with a much improved ability to communicate by Vietnamese!

Any thoughts?
I'm a sucker for new ideas  
cheers
Kim