After retiring from their nursing jobs in 2005, Dave and Wendy Justice set off with the intention of taking a trip around the world. They flew into Hong Kong, then traveled to China and Southeast Asia -- and then they never left.

"We just enjoyed it so much we didn't really see the point of continuing around the world," said Wendy Justice.

So far, they've lived in Malaysia, Thailand and Vietnam. For the last two years, they've called Hanoi home.

The couple has been living off income generated by their modest stock portfolio and rent payments from a home they own in Tennessee. As they age, they plan to tap their Individual Retirement Accounts and Social Security benefits.

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But they say they still have "plenty of money for little splurges" like a weekly housekeeper and dinners out. Their cell phone bill is only $3 a month, while they pay only $600 a month to rent a 3,000 square foot home.

Their biggest annoyance: "American pricing" where storekeepers try to charge U.S. expats more than locals.

Their adult children call them "crazy." But they say they have adjusted to life in Asia quite easily, having made a number of Vietnamese friends and they have slowly begun to learn the language.

"We get a lot of culture shock when we go back," said Wendy. "I prefer it over here at this point."