SpinDemWheelz I tried doing it one by one a while back and finished the last race and I had all golds and yet I never got a prize car. You still get money but you don't get a prize car. So yes, I am sure you need to participate in that series in order to win the prize car.
When i 1st started off,i bought a Toyota Vitz and raced it in it's series in the Beginner League and made my money that way.
It hasn't affected me in the slightest way...honest. :weird: