Carpet cleaning

Our italian greyhound absolutely hates the cold and the rain. He has, for i have no idea how long, been using the kids' room as a pee spot. I noticed a strong pee smell, but i mistakenly though it was the kids bedding, as they both have nighttime problems. After constant laundry for a few days, i realized it was the carpet. Then, one day my daughter had him in her room with the door shut. He started peeing in the floor right in front of her. I soaked up and cleaned what i could, but there is a large area in their room where he has peed and it dried there. It needs cleaned immediately, and i presume that i will need a cleaner again in the future because of his issue. I have been looking at carpet cleaning companies on Angie's List, but I am also considering just buying a carpet cleaning machine so that I can take care of it the next time it happens. Any recommendations on a carpet cleaning machine? Or perhaps against a particular one?

It probably soaked through to the padding underneath. So, cleaning the carpet won't completely eliminate the odor. Even if you can't smell it, your dog can, and he'll probably keep returning to that spot. Can you lift up the carpet so that you can clean the pad? You should soak everything with an enzymatic cleaner (Nature's Miracle, Kids n Pets, etc) and then let it air dry.

I have used one and a half gallons of Nature's Miracle. I need to physically clean the carpet, and then use natures miracle again to neutralize any residual odor. We had a very rainy beginning of the month, and I'm pretty sure that's when he was doing it.