Seems like a very expensive purchase for a guy not yet in the league and who isn't going to go all that highly to begin with.
He got an advance when he signed with his agent. $40K price tag is less than 2% of his projected salary next year. Reasonable purchase for a would be millionaire to his mother.
It is actually more than 2% of his projected salary. Speaking of his agent. He is taking at least 10%, the government is going to take 35-40%. He will need a place to live in his new city, transportation, probably new clothes, etc.
It is a nice gesture, but a foolish one for a guy who hasn't even been drafted yet.