A latest assessment by Japan’s Ministry of Defense into the construction cost of two Aegis Ashore sites found that the price has ballooned to $5.3 billion
By Commander, U.S. Naval Forces Europe-Africa/U.S. 6th Fleet (Aegis Ashore Missile Defense Complex Romania) [Public domain], via Wikimedia Commons
Tokyo will have to pay $3.6 billion for the two sites and after adding the price for purchasing the interceptors, the amount goes up to $5.3 billion.
The decision to use Lockheed Martin’s Long Range Discrimination Radar (LRDR) over Raytheon’s SPY-6 also increase the amount.