Pull out those removable floor mats. If they're cleanable, clean them. If they've got big holes in them or stains that only a flame thrower will obliterate, you're just going to have to buy new ones.
Fortunately, a new set of floor mats shouldn't cost you that much. A set of attractive rubber mats at your local auto parts store should cost you only about $20 to $30, said Kelley Blue Book's Alec Gutierrez.
Once that's done, clean the rest of the interior. Clean and treat the leather, if there is any, and vacuum and clean the carpeting.
Except for glass cleaner on the windows, don't use household cleaners in your car, warns Lauren Fix, an automotive expert who represents the Car Care Council. The materials inside your car are different from the stuff used to make the furniture and and carpets in your home. Buy cleaners that are made for the job.
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