As you know due to official purposes there are movement of families from one state to another. No one pays tax as taking NOC from one state RTO and Registering at other state involves lot of money and they have to bribe. I would suggest an easy online payment method where the person can pay 1 year or 6 months road tax so that each one will pay the tax since this wont be the trouble and will reduce bribery. Please treat this as a high priority and no cumbersome business should be involved!