I have one of these and I love it, it cleans up pet messes and works great in the car as well. I wouldn’t advise trying to use other carpet cleaning solution in it though. most of them foam and bubble up more than this machine can handle. The blue bottle of Bissel cleaner isn’t expensive and works great.
I also have this. And I got it from Woot! It is great!!! You just put the water and detergent in one side, put it on top of the stain area, hit a button and you can walk away for 5 minutes while it cleans the spot for you!
The ONLY downside to this, is that when done, it might show you that you could use a general carpet shampooing.