looking for the best sound deadening/heat reduction for the money. I see kits that cover probably a lot of the floor and I see people recommend stuff you get at Home Depot you cut and cover the entire floor.
That really looks like good stuff.This might generate some disagreement, but a lot of people have confused the asphalt-based 'peel and stick' roofing products sold at Home Depot, etc. with the real-deal butyl rubber based, foil backed sound insulation materials. They may look somewhat similar, but they don't provide the same benefits. Keep the asphalt on the road where it belongs. You can buy very aggressively priced butyl rubber sound insulation that performs very similarly to the big name brands. Here is just one example: https://www.amazon.com/gp/product/B00URUIKAK/?tag=fabo03-20
I don't think people are using roof tar paper from Home Depot. Possibly the tard foiled sticky paper for HVAC?...