What I did was first get a minimum of a pass on all enforcer tasks, then replayed hot pursuits due that each racer busted is 500 bounty and you can rack up if not already have the EMP, spike strips, road block and helicopter which each grant an additional reward of however much thousand bounty, also try rapid deployment because they usually have a distinction of 10,000 and are not to hard that it takes 5 minutes each time