Buy fatmat and do it yourself. It's really easy.

 

I payed a shop $50 to install the dynamat into my passenger door. He put it on the metal door on top of the membrane NOT on the plastic door panel. It is behind the door panel. He said it's where it's suppose to go. It DIDN'T work, the rattle is still there, nothing changed. He said it's because the subwoofer is mounted on the plastic door panel and the only way to get rid of the rattle is put something such as foam between the subwoofer and the plastic door panel. I just spent $100 for nothing. Furthermore, I realized the rear speakers make a buzz noise at high volumes, he recommended I get a baffle for the rear speakers. I want to take it to another professional shop tomorrow. Any suggestions?