Question if you charge each customer a standard travel time from the depot as if the tech always sets off from their to go to his site regardless where he comes from is that not the easy and fair way to do it then ever one knows exactly what is going on. The customer cannot be expected to pay for travel from another site because it could be quarter of an hour one week and two hours the week after depending where the tech is traveling from.
Also don`t know if this is a can of worms or not but who should pay for travel back!!