A $50,000 car is not going to make you win events, or even be competitive. Even if you do buy an evo.
I'm with Kato on this one. Given the events you've mentioned, I'd be buying a mildly modded A-reg car, and having fun in it, and learning how to drive a race car, in a race environment. Initially, whilst you're finding your feet, a $20k car's the go.

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