Praise be to Allah, the Lord of the Worlds.
Cars intended for keeping and personal use aren`t liable for Zakah no matter how high their value gets since amongst the principles of Zakah is that it is due only on growing wealth {Items set for trade}. Abu Huraira narrated that Allah's Messenger (Blessings and peace of Allah be upon him) said: "There is no Zakat either on a horse or a slave belonging to a Muslim." {Related by Bukhari}. An-Nawawi (May Allah have mercy on him) said: "This narration indicates that there is no Zakah on belongings meant for keeping" {Shareh Muslim, 7/55}.
Accordingly, no Zakah is due on the above car, even if its owner isn`t using it. Rather, his son will be using it in the future. However, if the father aims to evade Zakah, then Allah will hold him to account as He the Almighty Says: "And keep your opinion secret or proclaim it, lo! He is Knower of all that is in the breasts (of men). Should He not know what He created ? And He is the Subtile, the Aware." {Al-Mulk, 13-14}. And Allah The Almighty Knows Best.