An old hotel site in downtown Durham that has sat mostly vacant for years could finally get a makeover.Alliance Residential, a national apartment developer, announced Thursday it has purchased the former Crown Park Hotel and said it plans to tear down the old structure to make way for 342 luxury apartments. Alliance recently opened an office in Charlotte, and the project, dubbed Broadstone Durham, will be its first in the Triangle. “We’ve been tracking Durham since we opened the doors here, and we really love the fundamentals,” says Donald Santos, Alliance Residential’s Carolinas managing director.