I picked up this foam carpet freshner by PowerHouse at our Dollar Tree and it actually made the carpet smell really good. It dissolves on its own and you don't even have to vacuum. I am going to just because they need it but it really did freshen the rooms. It was enough for about two rooms and I sprayed it on the couch and DD's little chair. Not bad for one dollar.

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If I find in myself a desire which no experience in this world can satisfy, the most probable explanation is that I was made for another world.

C.S. Lewis

I use it all the time! The orange cleaner works well too.