The housing market here is very robust due to many jobs being linked to the government, often in groups which never see significant budget cuts. I anticipate a bit more deflation of property values, but not a crash.

HQ2-proximate properties will probably not be able to maintain their asking price, but I'm guessing property owners will do the NoVA thing of sitting on overpriced property long enough to try to squeeze as much out of it as they can.