Those custom installs start adding up real quick. I wanted a shop by my house to make a fab'd box of 8.3 cu in of volume space for this 12" Rockford Fosgate I had bought and they said $250, his quote was "Wood is expensive these days." have any of you ever been to any brand lumber supply yard? 30$ tops for a sheet of 3/4 MDF, the same stuff they would use. Also, they start racking up the price by adding parts you don't need. Like in that pic from Krypton kid, the Capacitior by the amp, is at least a 1 farad cap, and that Amp, not sure, but doesn't look like its over a 1000w. If your amp isn't pushing a 1000w+ a cap is USELESS. It will do you NO good and just adds to your price of install. So be careful and DIY is pretty easy with custom jobs for subs. Most lumber supply yards will cut the wood to exact specifications for you, and if you find the right guy will even do the math for you. Then its just laying down the wiring and not breaking the moldings.