In another thread ADM services said they had a lot that took less than two hours with 2-4" of snow and 10 hours with 12". I'm wondering if others of you find it takes this much longer for a heavy snow. If I charge based on 2-4" accumulations how do I cover myself so if we get an 8-12" storm I get paid for the work I do without charging T&M??? In Adm's case, I would have to charge 5x as much, or for five plowings. According to a book I have, the time would only increase from one hour to do 50,000 square feet at a 4" depth to two hours to plow the same area at a 12" depth. Do these numbers line up with your experience or would ADM's experience likely be more typical??? Is there an unknown factor that could have taken ADM longer (wet, heavy snow )? How do I plan for these things since I am generally going to be plowing 4" and less and base my per push rate on 2-4" plow times?