1 - Use the cheat UNLOCKALLTHINGS
2 - Enter any race day and exit once in it
3 - Go to your garage and you will have the Nissan 240SX you start the game with, the drag Chevy Cobalt SS, the drift Pontiac GTO, and the speed Dodge Viper SRT-10
4 - Sell them and you'll get over $100,000
This can only be done once per game, you have to take the disc out and put it back in the X-Box to do it again. That is the easiest way to make money.
no need to take out the game jus go back to the xbox dashboard menu and then start the game back up. u can also buy that acura for $0 and sell it for $7000 tht plus UNLOCKALLTHINGS i have like one trillion dollars i can buy every carin the game like 3 times and fix em up lol gets pretty boring with all the cash and cars but at least you can whoop the crap out of ur friends