The Republic of Korea Air Force received green light from Washington to upgrade 134 KF-16C/D Block 52 aircraft. That okay is necessary since the deal is made with an US based subsidary of British BAe Systems, making it fall under the US foreign military sales rules.
For a total cost of US$ 200 million South Korea initially only buys design of the upgrade program, or Phase 1. This phase will include detailed design requirements to include computers, displays, sensors and weapons, system design, pilot-aircraft interfaces, software design and development.
In other words: a lot of money for practically not the upgrade itself yet. That will be phase 2 and if the RoKAF will get the green light for that as well, the radar and avionics will be upgraded. What will be the price tag for the real upgrade is unclear yet.
Source: US DoD with additional reporting by AIRheads’ Marcel Burger