By Chris Nebenzahl and Justin Dean, Yardi Matrix While Denver has outpaced the national averages for rent growth and rental rates in recent years, the metro has finally begun to cool as significant construction begins to come on line and the rapidly accelerating economy eases. Market players echo this theme of slower growth, but Denver continues to plenty of opportunity. For the past few years Denver has been one of the nation’s best-performing real estate markets, as job growth and an influx of Millennials has sent demand for housing, office space, and retail sky high. Home values, too, have risen…