I sign up for the joint poly scheme when I was a. 17year old. They pay for your diploma school fees and also give you a monthly allowance. My bond is 6 years inclusive of the 2 years compulsory NS liability. I left at the age of 27yo with a private degree I paid myself and some cpf money for my bto house. If you do not know what you plan to do for your career, I feel that it is not a bad choice to sign on. Even if you feel that it is a bad choice you can always start afresh at the end of the bond when you are still 25 or 26yo(Exactly same age as your peers who decide to study a 3year degree FT after serving NS 2years)Just remember to eat,drink, sleep and leech fully when in there and it is highly possible u can save at least 50% of your income monthly. Invest smartly and if you feel this is a long term career for you, you can work till 60yo at a stable iron rice bowl job.