You should really try and do it yourself. I can't speak for body lifts, as I've never done one, but the suspension work isn't that diffucult.
Plus, since you put it together yourself, you'll know how to fix it yourself if anything goes wrong with it. Also, you'll have the satisfaction of knowing you did it yourself.
Oh, one more point. Eventually, you'll want to swap in different springs, or go higher. Then you'll have to pay an arm and a leg for labor all over again. I've torn my suspension apart 3 times already, and am planning on a fourth. Can you imagine how much that I've saved in labor by doing this myslef??
I REALLY think you should give it a shot.