That back yard was so steep...I would have suggested terracing all the way down. I see they wanted a pool and that caused a really forboding cave hollow. Vertical gardening elements would have cut out the harshness but I assume the owners aren't gardeners. Man imagine spending over $600,000 USD on a garden what I could do...I understand though that their lot was odd...hope their home was located in a nice location worthy of that much money being used.