No. it's never too early; or too late to start making plans for retirement. The early bird gets the worm, so the earlier you start saving and preparing for your retirement, the earlier you may be able to retire.
When you get your first full time job, it is a good idea to start thinking about retirement and how much you want to save up. Part of your pay check may already go to your retirement.
I'd say freshman year.
I'd say maybe in highschool, but a lot of people start eariler then that so I guess its just whenever that person is ready to do that.
I'd say whenever you want to!
It is not really a question of age, but of maturity. Nobody has a scinentifical theory or actual answer to your question. But i started making out at the age of 10. But if you really would like to...