I've lived in 2 places in Washington, DC that were haunted. One was an apartment in Glover Park, and the other was a house on Jenifer Street NW. I would have thought myself crazy except that my roommates corroborated my sightings with sightings of their own. The ghosts never made noise, but they made their presences known.
In both cases, we had the luxury of moving out due to expiring leases. OP, I'm guessing you might not be in the position to move out immediately. I found this site for the
Society for Paranormal Investigation (they've got a local branch, who knew?). Maybe it's worth a try?