Question
I have an area approx 275 sq ft that we took out the lawn to lay a patio of 8 x 4 inch brick.  The backyard slopes,  we have two corners to deal with from the house.  In addition and the cut we made of the grass is somewhat circular. We having a sandy soil, but I am bringing in 1.5 yards of washed sand to lay as a base.  Our problem is, since the water from the front drain's to the back yard, we have an angle/sloping that we need to deal with.  I know it is 1/4 inch slope per foot, but we don't know how much sirt/sand to dig out at all the different points.  

Uncovering the dirt fromn the start of the stoop, we have exctly what we need: 1.5 inches sand and the 2 inch brick with matches up evenly with the stoop.  The calculatons is what we are stumped on-and I don't know if we need to bring in professional for advice because we want to do the work ourselves. Appreciate your help and reponse.
Johnny J.

Answer
Hellow, Jonny -

I don't quite understand what area or volume you are confused about...

1-1/2 inches of sand for 275sf should be 1.3 cy, so you are in the ball-park with 1.5 yards.  

As to how much material needs to be removed & from where, it is hard to say from your question.  Here is a handy site for volume related landscape materials:
http://www.hedbergaggregates.com/DoItYourself/ProductCalculators/LandscapeProduc...

here is another one:
http://www.mycalculators.com/ca/landmatm.html

If I had to take a wild guess, you'll want to dig out at least 5.5 inches - 4 inches for the brick, and 1.5 inches for the sand. The extra sand will go inbetween the brick cracks once you've installed them.

And, since it is such a small area, you'll pay a LOT for professional advice.  We call it the "Fuss Factor Mark-up"

~Marc