By Alison Rice. M.D.C. Holdings, one of the 10 largest builders, just got bigger. In April, the Denver-based company bought the Las Vegas and Salt Lake City operations of WL Homes, based in Newport Beach, Calif. WL closed 561 homes in those markets last year.

And in May, Lennar announced plans to acquire Pacific Century Homes, the top builder in California's Inland Empire. Terms were not disclosed; Lennar is still completing due diligence.