Before the update, I completed 100% of every series except the two that require the 427 Cobra (waiting for it's weekly showcase). I had 1274 GC saved up. After purchasing the F12 for 256 GC, upgrading the Aventador with 97 GC to complete Battle Italia, and re-completing the TT's, leveling up a couple times, and watching a few videos, I'll have 1155 GC. Thus, the net cost of this update is 119 GC (for me). It also cost around 3 million R$.