The certificate of title of such vehicle shall be delivered to the person, firm or corporation holding the first lien or encumbrance upon the vehicle and retained by him or them until the entire amount of his or their lien is fully paid. Thereupon the certificate of title shall be delivered to the next lien holder, and so on, or if none, then to the owner of the vehicle. It shall be the responsibility of each lienor upon the satisfaction of his lien to deliver said certificate of title to the lienor next entitled to the possession thereof and, if none to the owner, which acts of delivery may be accomplished through registered or certified mail addressed to the lienor or the owner entitled to such possession at his address as shown upon said certificate. In the event of assignment of the obligation by a lienholder who lawfully has possession of the certificate of title at the time of assignment, the lienholder shall deliver the certificate of title to his assignee who shall be entitled to hold the same until the obligation is satisfied, at which time the assignee shall deliver the certificate of title to the next lienholder, or if none, then to the owner of the vehicle. In the event of assignment of the obligation by a lienholder not entitled to possession of the certificate of title at the time of assignment, the lienholder shall immediately upon becoming lawfully entitled to, and obtaining lawful possession of, the certificate of title, deliver the same to his assignee who shall be entitled to hold the same until the obligation is satisfied, at which time the assignee shall deliver the certificate of title to the next lienholder, or if none, then to the owner of the vehicle.