it is an action that I don't think is too good because you sell a car that you can use to work with that car. You can get more money and it will definitely be safe because the risk is not too high, different from you playing on bitcoin, the risk is very high.
He can buy more cars better when he succeeds or he has to use his old car for a long time. We can't advise him precisely in this case because this is a difficult decision and risky.