GL getting someone to do it for $200. Especially if this is the first time the plenum is coming off, the pull is going to take a while. It took me ~8 hours for my TT, but there was also a steeper learning curve. Even if they're experienced, if you have all of your old coolant lines, old PCV hoses and EGR (which you definitely need in Cali), its going to be a pain. With all my deletes I can now get mine off in under 2 hours by myself and about 1.25 hrs with help. Putting back on probably runs 1.5 hours.
All of that is just for the pull and put back together.
Now, for the second part, you can't say "both" of your valve covers are leaking, because there are 4. 2 for intake, 2 for exhaust. The parts are actually pretty cheap, for $50 you can get everything you need to do all 4
http://www.conceptzperformance.com/Cart ... 164.64.142. Check out z32.wikispaces.com for more about replacing them. Basically, what KILLED me on time on these was cleaning up the RTV from the exhaust valve covers. You have to be careful not to get any RTV chips into the valve cover area, and then lots of the places are about impossible to effectively scrape and clean at. I probably spent 1.5-2 hours per exhaust valve cover cleaning up RTV. Also, getting the screws off, and ESPECIALLY getting the screws back in to the exhaust valve covers are a TOTAL PITA. I'd recommend picking up some spare screws and washers, because you're going to lose a couple down, and they won't show themselves until the car moves again. All in all, replacing the cover gaskets themselves is not a technically difficult task, just a time consuming one.
So hopefully you can see why the shop quoted you $$$ for the job, and also why you'll be hard pressed to find someone to do that for $200 if they know what they're getting themselves into. It's going to be time to learn some new fun stuff about your car, and get tearing into it yourself if you can't afford or don't want to pay out for it!
Edit: I just realized that if you are keeping your EGR pipes (again, you have to in Cali), then you also have to disconnect/reconnect them to be able to get at the last exhaust valve cover screws. That is going to be a TOTAL PITA. Hopefully just your intake valve covers are leaking, maybe you should verify with the shop which ones they identified.
