At times you may need to make alterations to the allocated route.
This could include extra tolls or extra distance charges for any deviations from allocated route.
As long as these alterations are agreed up by yourself and the passenger, you are within your right to charge the passenger extra on top of the fixed fare quote.
To do this you will first need to to complete the booking and then select take payment to charge the extra amount. See How do I take a payment for a rank/hail job?
Remember if a passenger does not request the change in route, it is not fair to charge them extra, so please do not do so.