The Purple Line was supposed to take riders between Montgomery and Prince George’s counties this year, but the light-rail project is four years behind schedule because of labor disputes and rising costs. This week, the construction union and contractor signed a new bargaining agreement that will kick-start the idling project. WTOP’s Luke Lukert tells us where the Purple Line stands. We also speak with realtor Ron Sitrin about how the long-delayed project is impacting nearby real estate.