There is a common belief, a misconception really, that hiring professionals for carpet cleaning is both inconvenient and costly.
You can do it yourself. Just go out and hire a steam cleaner and browse through the local hardware store and buy a few stain removal products.
To be able to do a fair comparison between DIY and using professional cleaners we really need to look at the differences between the two actual processes used to clean the carpets so as we can draw a fairer conclusion.