just an idea...before the gate I would imagine there are realtor signs somewhere close by or at the gate area. Personally , I would call the realty company and see if they can help you get connected to the right people. Sometimes homeowner assoc's dont get up and running until after more than a few homes are occupied.
If you are lucky enough to find one of the realty persons who will help you that would be great...but...dont be surprised if the real estate agents blow you off. Put on your thick skin and see if you can get your foot in door.