The telescoping brush I've seen and although a little flimsy does work decent.
For the interior you can go to any store that sells a general carpet cleaner (Wal-Mart, Target, Dollar Store, etc.) in a can or spray and depending on how deep set the stain is apply by spraying, lightly dabbing, letting dry, and vacuuming up. Read the directions and you'll be fine. I recommend the Bissell Carpet Cleaner. It comes in a white and red can.