Dont buy in stages... By the time your done the prices for somethings could have changed, and/or you find something else that would have been better. Just save up one big ass amount of money and buy all at the same time. You dont know you might have more money left over than what you would have had with buying in stages.
Besides, what are you gonna do with the parts you got now... Read the manuals 10 times each? lol.