The number of houses bought by developers ready to put up new development in their place continues to drop in South Florida. Renovation, instead, is in vogue. Teardowns, once popular in pockets of Miami-Dade County — Coconut Grove, Coral Gables, Pinecrest — along the waterways in Broward County, and in Palm Beach County are on the decline. In Pinecrest, for example, there were 45 teardowns in 2006, 33 in 2007 and only 12 so far this year. At the same time, though, sales of existing homes have declined over the past three years in the United States, and were down 12.4 percent in the first half of 2008 compared with the same time in 2007, according to the National Association of Realtors. In July 2008, sales were down 22 percent in Miami and up 4 percent in Fort Lauderdale, while prices were down in both cities — 19 percent in Fort Lauderdale and 14 percent in Miami.