Lower cost carpet options???

Make sure your car doesn't leak any water before installing any type of mat under your carpet. That stuff will trap moisture and rust your floor boards out.

Noted. Found a leak when I washed it at the passenger Window. The seal was cracked and worn. Repaired the seal for now. Sprayed it with a hose to see if it would leak again. Nothing so far but I am scouring the car. I thought the trunk leaked, but turned out it was standing water left over from a broken water bottle I had in there.