Adding to the ever-changing skyline of San Francisco's new developmental "it" zone is a nearly completed 16-story luxury rental tower in the city's booming Mission Bay neighborhood . Azure Apartments, which includes the tower and a completed five-story low-rise structure, offers 273 units and 396,200 square feet of for-lease residential space targeted to young professionals commuting to the city's Financial District and South Bay, said representatives from project developer Equity Residential .