Artificial grass/astro turf?

I have a small garden which i had turfs put down 2 years ago, but i have 2 pets... dog and cat and the grass started to rot even though i watered it every time my dog done a wee on it, i really don't want to get turfs again. Someone suggested wood chip but after i researched it most people said it rots and smells and i don't want gravel or stones. I was watching 60 minute makeover last week and they put artificial grass down in the garden for 3 lads to play football on and i heard them say it was ok for animals to go on. I will only be covering 15 foot by 25 foot. Has anyone had this in there garden and know where the best place to get it from and how much it is also can you put it straight onto dirt or do you have to put the black plastic stuff down first. Thank you.