If you want lots 'o cash do this....
Go to "Special condition races" I think it's on the far left middle of the "map". You may need a little more license than you have now and if so simply get it by comlteig the tests for it first in "license center"
Anyway, the second race in the special condition races is "capri". You only have to beat the one car for the two races and when you do you get a Toyota Rally car that you can sell for $260,000!!!! And............you can win it over and over
There ya go, enjoy/