This video gives you 5 great tips to keep in mind when using a rented or home carpet cleaning machine. As a professional carpet cleaner in Tampa FL I tell my customers that these machine do a good job of cleaning their carpet but that soapy cleaning solution creates more problems then it solves. I have used these machines in my own home several years ago and they can be used effectively, but be prepared to put in the hours to get it done well.
Carpet cleaning rentals have improved in the last 5 years but the solutions are still the down fall. This video recommends spraying the carpet cleaning solution down first, then extract it with the carpet cleaning rental. I agree. I use pre-sprays on almost every carpet cleaning job I do. It makes a huge difference on those heavily soiled areas. Clean warm tap water in the in the rented carpet cleaning machine is all that is needed. Like the video says don't forget the dry pass.
When it comes to pet urine I agree that an enzymatic cleaner is needed to get the job done. I have never used the one recommended in the video but your pet supply store carries several brands of pet urine cleaner that you can choose from.
After cleaning your carpet with a rented carpet cleaner you might feel like it was more work than you wanted to do. Consider hiring a professional carpet cleaner instead. It can be a lot of work so take it slow and carefully.