 Shares of Redfin Corp. RDFN, -5.50 slid 5.4 in morning trading Thursday, after the technology-powered real estate brokerage said home sales suffered a record monthly drop, as elevated housing costs kept buyers and sellers on the sidelines. The company said that on a seasonally adjusted basis, home sales in November fell 35.1 from the same period a year ago, the biggest year-over-year drop in Redfins records dating back to 2012. 