Hiring a vehicle for a purpose is a contract between two persons. It is defined as “Bailment” under the Indian Contract Act 1872. According to 148. – A ‘bailment’ is the delivery of goods by one person to another for some purpose, upon a contract that they shall, when the purpose is accomplished, be returned or otherwise disposed of according to the directions of the person delivering them.
It is purely a case of civil nature because it is a contract. Charging higher than other is an act of “Fraud” defined under section 17 on the Act. It is an avoidable contract and the party who is deceived by others has the right to put himself in the position in which he would have been if no fraud had been committed. The contract is not voidable if a party to the contract whose consent is taken by fraud had the means of discovering the truth with ordinary diligence.
In your case, you have two options to sue him. You can file a civil suit for declaration of the contract void and recovery of money or you can file a complaint before consumer forum for recovery of excess money charged by another party.
Consumer forum proceeding is best suited for you. Filing a civil suit required court fee is proportionate to the relief claimed and also it takes many years to decide. The consumer forum has short proceeding, it works swiftly and it requires 100 Rs. as court fee.