every subaru is going to be over the blue book value. these cars go used for as much as a new one usually. esp the sti. will this be your first car? just asking you seem young based on your post. if it is your first or even second car. hell if your under the legal drinking age. i would highly, highly recommend you do not buy an sti. lest you end up like your friend. the regular wrx is a little more forgiving. and cheaper lol. ordering one isnt the end of the world. at least you'll know its on the way!
oh and welcome lol