re: At what point do you cross over to excess?

I think if you let material goods define you, you've crossed the line.

If you think some manufactured product will make you happy, you likely will be disappointed.

I recommend experiences over luxury items like cars, jewelry, etc. Enjoy time with the people you love. Travel with a friend. Help the needy. Look for ways to serve others. Coach a team. Volunteer.

At the end of the day, if you are just, kind and humble, you probably won't go overboard.