Take the car back...part it out...use the money towards a car you can actually afford...put the rest in savings.

Trying to buy a car above and beyond your means is just plain stupid and shows that you are immature and irresponsible with your money. Once you have bought an M3 then what about your insurance costs, maintenence costs, etc?

I seem o remember you talking about being in over your head on the Teg anyways so why double that with an overpriced car you really can't afford?

Finish school and during that time live within your means, you will thank me later for this advice even if you hate me now for my honesty