Selling a car to someone you know is a bad idea. There are plenty of reasons for that.
The first reason is the money issue. Such a sale and purchase will necessarily happen only after the bargaining. A customer you know will be hoping for a good discount. And this should not lead to the fact that you can lose some of the money in the sale. This situation will simply lead to a breakdown in your relationship with the buyer, who is your loved one.
The second reason can be called a technical malfunction of the car. The car can break down at any second, and even a seemingly perfect car may need to be repaired after some time. The reason for this may be careless handling or just an accident, but everything will be perceived as a deception. This will significantly damage the relationship with the person who bought the car.
And the third reason is the buyer's request to replace any part, be it a mirror, glass or wipers. Explaining that when buying the car was quickly and poorly inspected. And you, in order not to upset a relative and not to spoil relations with him, will still have to change this detail. It seems that it is no longer the owner, but time and money will go to the car of the new owner.
Therefore, you shouldn't sell your car to a relative, colleague or friends. This is the worst option of all, but it's good that it's not the only one.