Crush his creativity?
No, inspire him!
Teach him that a first try at anything, no matter how good it is, is stilll a first try.
He must keep it so he can learn how he improves.
And set a goal of how many he needs to make before he sells
Another lesson is because someone will buy it does not mean it is sellable.
What quality does he have the patience before he will want to sell it.
And all of this is a fine balance for a father to teach a 7 year old son
Good Luck
No, inspire him!
Teach him that a first try at anything, no matter how good it is, is stilll a first try.
He must keep it so he can learn how he improves.
And set a goal of how many he needs to make before he sells
Another lesson is because someone will buy it does not mean it is sellable.
What quality does he have the patience before he will want to sell it.
And all of this is a fine balance for a father to teach a 7 year old son
Good Luck