hiiiiiiiii,
Welcome to Expat.com !!!!!!
I don't know about living standard of Vietnam or Cambodia
But i can explain you about Myanmar . . . . . .
Now days living cost in Myanmar is rising high day by day
foreign companies are coming to Myanmar to establish there business
if i talk about house rent, car rent or other thing, it all depends on you that which kind of living standard you are looking . . .
Like currently i'm living in Yangon (not now . . . i'm in India for few weeks) i have a rented home in Yangon i'm paying 350$ a month it is 1 room set along with attached bath & kitchen . . . . .
i spend $450 in a month for food (Indian meal)
$ 100 for electricity and water bill
$ 50 for mobile
traveling expense is depend on my schedule . . . . . .
Regards
UNOHU