Also, if you're in MOCO, post at places like NIH, JohnHopkins, American Cancer Institure, Walter Reed, etc.
There's usually a steady influx of doctors from other countries who get 2 or 3 year contracts, and need to look for a place that's local.
If you're in VA, do the same thing with research hospitals by you.
Also... let all the embassies know that you have a vacant rental.
Maybe one of them is looking?