I have read every post on retaining walls and still can't find my answer. I am going to quote a wall for one of my customers and was needing a little help. This wall will run about 85' long, here is my question. If i were to tie a string from one end to the other, there is about a 2 1/2' difference in elevation. Does the base for the entire wall need to be at the same level, does this make it easier and is it usually what is the normal thing to do? The wall above grwond will actually be stepping down a little the more the elevation drops. So...... In my example with the 2 1/2' of elevation difference, I will end up having 2 1/2' of block under ground where the elevation is highest, right? Any advice will be appreciated!