If you own a Toyota product and you're a do-it-yourself kind of person, you can easily save some bucks by replacing your own cabin air filter. The same would probably hold true regardless of what type of car you have!!
I ordered a bunch of them from a place called Logical-Source
www.logical-source.com . I paid right at $50 for 7 of them, no tax, including shipping to my door. I got lucky - we own a Scion xB and a RAV4....and they both use the same cabin air filter. If you drag your feet, the 'Out with the old and in with the new' job on either of these two models will take you 10 minutes max. Real simple - the filter resides in a little compartment behind the glove box. Glove box removal is very easy - no tools required. Pop the lid off the filter compartment, old one out, new one in, pop the lid back on, reinstall the glove box......easy peasy! They even include instructions with helpful photos with the filters. Granted, these are aftermarket filters but they seem fine to me! They're not "mission critical" to anything other than filtering the outside air coming into the passenger compartment.
I was SHOCKED when I first changed ours out - they were filthy! So I change them now every 10-15 k miles.
Bill