Before you start asking for cars on the Marketplace, I recommend that you take a look at The GT5 Blacklist Thread to learn what can and cannot be traded.
The Red Bull X2010 is unable to be traded, but can be earned from the Red Bull X1 Challenge Special Event which unlocks at A-Spec Level 30. You can get 3 different X1s from that event:
Red Bull X2010 S. Vettel (earned by achieving bronze on all events)
Red Bull X2010 (earned by achieving silver on all events)
Red Bull X2010 Prototype (earned by achieving gold on all events)
You also earn a free one (S. Vettel version) by reaching B-Spec Level 35.
The only other way to get one is to hit A-Spec Level 40 and buy one from the Dealership for 20 million credits or buy the DLC and get the Red Bull X2011.
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