I have a customer that wants a wall running down the property line going from about a foot high to about 4-5' at its highest. he then wants to install a fence along that property line (on top of the wall). Thats my first issue (fence). My second issue is that he wants the wall to run straight and not curve around with the curve of the slope at the back of the property. I will explain: The property was raised at some point and the back yard drops off about 6'-8' at the rear of the property. this drop off wraps around and runs up the property line gradually decreasing as you get nearer to the house. he wants the wall on the side only, not along the back drop off. I know this sounds basic, but I feel like I will be forever worrying about erosion from the back of the wall running down the rear slope. any suggestions or ideas? or moral support?