Getting the right mobile phone number is becoming a pricey fad in once-impoverished Vietnam.
The country's small but growing nouveau-riche class are paying as much as US$7,000 to land a so dep, or 'beautiful number'.
Those with more modest incomes - the national average is about US$500 a year - pay US$25 to US$100 for a number deemed lucky, easy to remember, or both.
'It's been lucky for me so far because I've moved to a better working environment,' said Hanoi's Nguyen Duy Quynh, who paid a premium of US$95 a month ago for his 337 7993 number.
Repeated digits and numerological correctness are the main factors in a number's desirability. About one in 1,000 random numbers passes muster. Phone shops set the special numbers aside and slot them in price categories, provided on a list for customers to browse through.
'On average I sell four or five per month,' said Lam Tuan, manager of one of the growing number of small phone shops in the capital, Hanoi.