A very large percentage of wealthy Miami home buyers are from overseas, and a huge portion of those foreign buyers pay for their homes in cash, according to one realtor from the area.
Speaking of her own experience with high-end buyers, Patricia Delinois, CEO of Century 21 Premier Elite Realty, said that "62 percent of the buyers are from overseas, and 90 percent of those buyers are purchasing homes in cash."
Delinois, told CNBC's "Power House" that said "cash is king" among buyers who hail largely from Brazil, Venezuela, Argentina, Canada, France, Colombia, Mexico and Peru. (Delinois made no mention of Russian buyers, who have been prominent in the market in recent years.)
"Power House" shined the spotlight on Coral Gables, which is southwest of downtown Miami and home to the University of Miami.
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According to the Miami Association of Realtors, at the end of April in Miami-Dade County, the median sale price for a single family home was $243,000. That's up 8 percent from 2013.
The median days a home is on the market is 43, with a 5.5 month supply of inventory.
—By CNBC's Katie Iacovella