Depending on what type of system you want and how big, 6500 isnt too bad for that as long as its a good company doing it. Chuck in a truck with two ladders and no common sense will install a piece of **** that won't make it past the warranty period for half that.
I actually had trouble finding someone years ago ... and naturally, calling your full service dealer is not going to get you a practical price. With a regular split system the lines are not just soldered .. not DIY for most.