Enter any type of pink slip race (for example, the sprints). Once you select the pink slip race, remove your memory card. Select "OK" for the race, the no memory card found message, and disabling auto-save. If you lose the race, exit back to the title screen, insert your memory card, and it will load your career with everything you had before the race (car and respect points)/ If you won, exit to the career screen and select "Extras" to enable auto-save. Keep doing this to get a lot of cars or sell them to get money quicker.