He totally believes in it and tells that then he could buy not only a new car but a flat also.
Does it really worth it? He uses his car for his work and now he wouldn't be able to do this anymore as he thinks there's no need to work anymore.
It would be less likely that the price would reach that amount and I think he made a rush decision. What is he doing now by the way since you said he is thinking there's no need to work. Did he stop working now or not? He should have invested something he do not need so that he would not be emotional in case the price went down further. How long can he wait to reach that amount?