You are the CFI holding the reins and you are responsible for correcting the bad behavior early on! Remember the law of primacy - the habits we learn first stick! I don't think addressing the issue this late in the game will help because he's accustomed to breaking the rules.

I made the same mistake with my very first instrument student. He was regularly late and didn't study or do his homework, but he was a good stick and fun to be around, so other than the occasional reminder to work harder, I let it slide.

I waited too long to confront him, and when I did, he lost his **** and completely blew up. We had an argument, but I eventually got him to apologize and admit he was wrong. After that, he no-showed for the rest of the semester, so I charged him and failed him for the course.

He accumulated so many absences and tardies over the next year that he dropped out of college completely.

According to his Facebook he's a "Customer Service Representative" at Denny's. The irony is that he's home every night and probably makes more money than I do, but that's beside the point

The harsh reality is that some people are pricks, plain and simple, no matter how much we want to like or help them. They do not care about success or working hard, and will disrespect you and waste your time. It is not your job to be friends with these a**holes - it is your job to identify them, discipline them, and, if you can, teach them. Good luck.