I don't have experience, but, if I were you,

I would not buy him any of "PSII, MP3, 手机, IPOT, 狗, 车". He should get a job and use his own money for those. I don't think it will make him "感到自不如人或自卑" if you ask him to work for those.

An ex-co-worker (engineer), now a stay-home mom, recently mentioned that she might try some art-related job after her kids is old enough. She loves art. The reason for her to become an engineer is, during her high-school years, she worked in fast-food place. She realized that minimum wage job is not enough for her. Your son needs to understand that.

Also, if possible, tell him that you plan to retire early. You can only support him till 18 and maybe pay half of his college. You are going to use up all your savings. You won't have anything leave for him.