I've had a bit more time to look at this one and from what you are saying mike you are actually out by approx 1200 yd³. As your excavator is saying you need 1000yd³ to be brought onto the site and your analysis is saying you will actually end up with 200yd³ to get rid of (cart-away it is often called).
I have been going over the site plan trying to account for this discrepancy but can't fully. I redefined the road using break-lines, and made adjustments to the outline like Leo suggested. I also separated all the items out into separate phases as Tim suggested so we could analyse them separately. This is what I got :
Landscape area around the property :
Cut : 219.79 yd³ Fill 810.14 yd³ Net : 590.35 (fill)yd³
House dig to marked basement FFL level :
Cut : 516.66 yd³ Fill 0yd³ Net : -516.66 (cut)yd³
Garage to marked FFL.
Cut : 8.20 yd³ Fill 16.26yd³ Net : 8.06 (fill)yd³
Porch and Patio to marked first floor FFL.
Cut : 0 yd³ Fill 91.18 yd³ Net : 91.18 (fill)yd³
TOTALS FOR WHOLE PROJECT
Cut : 744.62 yd³ Fill 917.58 yd³ Net : 172.96 (fill)yd³
Obviously material thickness\sub grade need to be taken into account. Over the road that will reduce the fill, over the basement that will increase the cut, however I can't see it making up to the large difference between you and the excavator. Let me know the surface material thickness and I will add them in.
Let us know the updates on the project, it is always interesting to us to compare the digital modelling with real world results. There are a lot of other factors relating to site and soil conditions that your excavator might be taking into account that we are not here in a mathematical computer model.
One thing I might suggest is to send him a download of Kubla Cubed Lite (it is free to use). This can be used to open Kubla Cubed Professional files, although he will not be able to edit the Professional elements he can view them. Over the phone you can then talk him through how you have broken it down, he might have some input on where your methods differ and you can revise the model or he might revise his estimate seeing the 3D model. Kubla Cubed uses the Prism Volume method using two Triangulations, this is considered to be the most mathematically complete model.
