“Owner” means a person who holds the legal title of a vehicle, or in the event a vehicle is the subject of an agreement for the conditional sale or lease thereof with the right of purchase upon performance of the conditions stated in the agreement and with an immediate right of possession vested in the conditional vendee or lessee, or in the event a mortgagor of a vehicle is entitled to possession, then the conditional vendee or lessee or mortgagor shall be deemed the owner for the purpose of this chapter.