You shold be looking to pay 100$ to 150. I paid $150 for my install. The best place to go to get this work done is your local import shop cuz they'll do it quicker and actually know what there doing. When I was young and stupid I took my car to America's Service Station to put performance shocks on and they ended up puting some of my springs on upside down. I took it in for the 2nd time to correct the problem and they had 2 upside down and the other 2 right side up. It took them 3 times to get it right.
It's actually pretty basic. If you don't have the tools you'll need a good metric socket and open/box wrench set. Something from sears would be OK. A 2' 1/2" breaker bar. A 1/2" 17mm socket and wrench (I think it's 17mm for the upper link bolts on the front). A pair of plyers for the front break lines. A spring compressor (very necessary). Umm, an adjustible or 8mm wrench to hold the strut rod. If you really want to tackle it yourself let me know and I can probalby write something fairly good up for you.
I'm getting it done .. .I actually found a pretty good deal for a price around here. 220 for installation of lowering springs and mounting and balancing my new rims and tires...so I'll just go with thtat.