300 for everything (meaning mufflers, pipes, labor) all included is a good price. That's about what I paid for my setup. If the guy in the shop can weld and knows how to match up different pipe sizes and get them to fit together then you should be fine.
I had a problem with my shop. This was just a regular garage, not an exhaust shop. Long story short my car ended up in the shop over night because the installer had to go to another metal shop to get a 2.5" to 2.25" reducer pipe fitting custom made because he didn't have anything like that in the shop. Hearing my car had to stay in the shop overnight because of lack of parts really upset me. Lesson learned is make sure the shop has the right parts and tools before you let them start working on your car. Ask lots of questions that would seem obvious to you. Get to talk to the person that's going to do your install to find out if he knows what he's doing or not. Also get a price quote in writing. That way they can't jack up the price of your install after they run into a little difficulty with the installation. Shop around for the best place where you find a good price and know that the shop knows what there doing. Then you can save your self the grief of arguing over your car and being unhappy with the install.
