The scrubber materials including ducting where about $45-50 The carbon i got for super cheap because it was on clearance at my work. It was a 36oz. pack of activated carbon and i probably only used about 1/3 to 1/4 of the whole pack. I saw 28oz. packs of activated carbon at petco for 9.99 I'm not sure how well it works because i don't have it hooked up and my plants don't even smell yet.