Stewart Hayes's decision to leave the U.S. can be traced back to a chance encounter on a vacation to Costa Rica he took more than a decade ago.

Hayes had already fallen in love with Costa Rica on an earlier vacation with his two sons. When he returned, he fell in love with a Costa Rican woman. The two married in 2002.

The couple lived together in Redding, Calif. for a decade. But as Hayes started adding up the health care and other costs he would face during retirement, moving to Costa Rica started to make a lot of sense.

After retiring from his job as an insurance inspector, he and his wife Mayela moved to Costa Rica, where they purchased a 3,000 square-foot home for $235,000 three years ago.

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Now the couple lives mainly off his monthly pension of $1,300 a month and rental income from their California home. He also recently invested in a shaved ice truck franchise, which his son operates in Reno, Nev.

The couple pays only $90 a month for public health care coverage. The waiting list can be long for some procedures though, but he said paying out-of-pocket for private medical care every once in awhile is still cheaper than the U.S. He recently had cataract surgery, for example, for only $2,000.

Plus, he said he loves the excitement of breaking out of his old routines. "I couldn't see myself being in the same house in Redding for 35 years and dying there," he said.