Cost for dual exhaust?

I bought a dual exhaust kit through jegs which was around the same cost as the summit kit 72Blu is talking about (around 250$).

My 318 came with a y pipe/head pipe deal. I cut the head pipes after the drop and within the strait section of the pipe (before it turns into the y). I plan on welding (but can be done with some clamps) a 12 or 24 inch section of pipe on to the newly cut head pipes to connect the jegs/summit header back exhaust system. Save from having to buy head pipes from accurate exhaust for 100$+

If you would consider DIY. But I guess it gives you a idea how much it should cost too.