Scott Galloway was pretty confident that it was always intended to be in Washington, partially because of Jeff Bezos already owning a house there: https://www.youtube.com/watch?v=_HyiY_m_YxI&t=542
It's got nothing to do with whether or not Bezos can buy a house in a given location. It has to do with examining the existing incentives that led Bezos to buy a home there in the first place, and applying that logic to the requirements of HQ2.
