How much is the toll fee in NLEX?

Could you please provide some insight into the toll fee charged for using the North Luzon Expressway, or NLEX? Is the fee consistent across all entry and exit points, or does it vary depending on factors such as time of day, vehicle type, or distance traveled? Is there a specific payment method that is preferred or mandatory? Also, are there any discounts or exemptions available for certain individuals or vehicles? Lastly, are there any upcoming changes to the toll fee structure that drivers should be aware of?