Big Bucks!
Earn those big bucks.

This trophy requires you to accumulate a certain amount of cash, the exact amount can be found in the My Stuff section under Trophies where it will say how much you have against how much you need to get, for example 234000/666666. To get this trophy early just dont spend a penny for your first few races until it pops, they are easily winnable with the early cars. If not, you will probably get this trophy naturally but if you do happen to miss it you can win a few races to rack up the cash.