Stop in for a cup of coffee

Whats everyone using for sound deadener/insulation that doesnt cost an arm and a leg. I've seen something about what you can buy at the local home store, but looking for options. I need to get something in my car so my feet dont get so damn hot.
I used this on 66 Dart,
https://www.amazon.com/dp/B0751CBXBT/?tag=fabo03-20