Just reading thru this, I haven't heard what kind of material and what kind of compaction it has. Your amount of time will be greatly affected by the material. If it's compacted tight, it will take longer with a smaller piece of equipment to get it loosened up to work it. You could reduce some time by adding weight to the box blade to make it easier to rip.
Also, are the potholes caused by poor subgrade conditions? If so, he would be better hauling in another load of material and filling the holes. As far as price goes, location determines some of it and how hungry you are determines some of it. [emoji16]
In my opinion, if you're unsure, it's better to under price until you get a "feel" for it. It's easier to increase your price after you've worked for someone, than to lose the business to over pricing. Even at $40/hr you can learn a lot, secure some business, and increase your price.
Just my opinion.
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