Yes, you need to buy the climate controls. The USDM climate controls and HU are on the same circuit board, so buying them separates it out, which you do have to do. Its stupid, I know, and the only thing that has held me back on doing this as well (bought the car specifically w/o Bose because I knew I was going to want to upgrade at some point). As for the JDM trim piece, I would make sure they have it first before you buy anything else. From what I've heard elsewhere, these aren't available at the moment and indefinitely. There are knockoffs out there, but they have rubber buttons, which are gross. I wouldn't recommend having it installed at Best Buy or any retail store. Go to a dedicated, well-known car stereo shop to have it done. I would say $75 would be about average, I had a stereo installed and it was $50 per unit (had a HU & XM installed for $100). As for cameras, the cheapest you'll probably find is $100-150. Here's a list of cameras; as for recommendations, I really don't have any.
http://www.crutchfield.com/App...=True
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