I am trying to put together a bid on a new lawn to fix what some contractor did it is real ugly. The contractor removed all the topsoil and put it on his lawn he lives on the same street of 8 homes he has the only decent lawn on the rd. Here are my questions I have never used a Harley rake before. The lawn is so rocky nothing will grow they range from small rocks to water melon size the square footage of lawn is 48,000 sq ft. From what I have seen its going to produce 40-50 yards of rock. What can I expect to do per hour with a Harley rake as far as going over the lawn? And how much build up can I get before I need to start making a pile for all the rocks that are getting in my way? As you can see we have a little over an acre what I am trying to figure out is how long I am going to be on this phase of the job so I can price it correctly and since I have never done this before I cannot fall back on personal experience.