If I was you, I'd sell the E46, buy a small used car that doesn't require much maintenance and has already taken its biggest deprecation hit. Then save save save for a while, and lease a USED M3. It's not the end of the world if you can't get it straight away, I was 16 when I first saw the M3 in pictures, decided to buy a 325XI when I was 18 because I felt like the M3 wouldn't have been a good choice due to insurance etc and then this year I brought an M3, only 20 years old. Good luck, and don't forget what others have already said, your net worth matters more than your salary because if you lose your job you'll be stuck with rent and car payments, with no-where to go.
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