I'm new to working with new lawns and a homeowner has asked for some help getting their grass going. The sod in the front is very hilly and has a 6" deep sink hole about the size of a grave. I don't know when the sod was laid down, but it isn't in very good shape. With the sides and back, it's graded to a pond behind it. The sides and back are so full of pebble sized stones I don't know how the builder ever left it like that. I will recommend tio the homeowner that she raise hell to the builder to dump some dirt(good stuff)and regrade, seed, etc. Would there be any concerns with erosion that the dirt on top would just move the rocks back on top? OR should I just bust my tail and use a rake and get up as much of it on my own as I can? Recommendations greatly appreciated. Thanks!!!