Don't use any "deadener" from a hardware store. If you want to do it right the first time, then you're going to pay for a top-notch deadener. I'd personally go with Sound Deadener Showdown if you want to do it all right. The owner, Don, will help you figure out exactly what you need for your goals, and treat you right.
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In the past I've used Audio Technix and it's been great for me. They've now changed names to CT Sounds.
For CCF, there's a handful of things you
can use that actually will work well. But car audio CCF is usually designed to keep moisture out, and it's just a bit more suited for the environment.
Other brands that would be good: Second Skin, Murder Mat, Raammat.
It looks like the AudioTechnix brand I was speaking of earlier, is available on
eBay:
24 Sq ft Ct Sounds 80 Mil Sound Deadener Heat Shield Square Feet | eBay
That's an 80mil pack so it's very thick, and heavy. the 24sq ft would probably be enough to do all 4 doors and trunk properly.
I know it's quite a bit pricier than whatever the hell that GTmat is that was listed earlier. But that only has a thickness of 50mil. Honestly, you'll end up having to use more of that and do more work, than you would with this product.
That's just my opinion from my personal experiences. That'd be the way to do it right. If you want to save a few bucks then go ahead and get something cheaper.