How much do new brakes cost on a 350z?
New brake pads will cost approximately $10 at a discount auto-parts store. The new brake pads and installation will cost approximately $30 per wheel at an auto mechanic shop.
I just had the front brakes 'done'. I called about 6 places, some named brand and some 'garage', and the average cost was about $130-$140. This includes new pads and resurfacing. Also realize my front brakes are disc brakes, my rear brakes are drum brakes. Drum brakes are about $50-$60 more. They broke it down to $60 parts $70 labor.
Bleed the rear brakes and add new brake fluid. Typically the brakes feeling as if they give too much or "squishy" is from small air bubbles in the brake line...so by bleeding and adding new fluid you let out the small bubbles which cause the squishiness. When you changed the brakes many people tend to hit the line as well as not clamp them properly and therefore render the brakes "squishy". Hope this helps. J