The reason for the savings is that 28 ft trusses are less expensive than 30 ft. trusses, and the 30 ft. truss required a crane to unload and place on the building. The 28 ft. trusses were placed by myself and two friends.

One thing I want to point out here is make good friends with the counter men at whatever lumber yard or home supply store you use. For me this was Menard's, because it is exactly ONE mile

Again, think about all your alternatives. Digging the trenches for the footers or foundations doesn't require a backhoe (and operator if you are not experienced) nor does it require days and weeks of manual digging. You can rent a ditch trencher (Ditch Witch) for about $50.00 for a half-day and do as good a job as a very experienced backhoe operator, if not better. You have to remember that any excess dirt you remove has to be replaced, generally with concrete, which is expensive. Since I had a trencher that would dig a 12 inch wide trench, and my site was level and compact (I have a sandy clay that packs like cement, and is just about as hard to dig by hand) I could set the depth gage on the trencher and go for it. Checking the depth with the transit showed only 1 inch of variation over the 160 feet of trenches. 

My method was to make my building site level first (and remove the grass sod). To do so I rented a "Terra-Mite" backhoe at $240 for the weekend. This is about a 1/2 size (Compared to the typical Case 580 class) backhoe with a front bucket. For the backhoe it does us twin joysticks for controls, and did give me a little trouble for the first half-hour or so as they are what is referred to a "Chinese Sticks." The controls work exactly opposite the poplar John Deere backhoe (a machine I have spent many hours on) joysticks work. Of course with a backhoe, no matter how much experience you have, you have to be attentative and careful every moment. Unless you really want to see what an out-of-control backhoe bucket can do the side of your wife's Corvette that is. The machine, with its 20HP Kohler Twin Cylinder engine, worked very smoothly, and never did lack for power. The nice thing is you can tow it with a 1/2 Ton pickup, though I would recommend using a heavy tow truck if you can get one. As a former over-the-road truck driver, the brakes on a 1/2 Ton Pickup are a little "light" to be towing this machine on a trailer. Most of the rental places will deliver it for you if you don't have a truck. 

Now for the planning sequence. I was going to cut the site down "to grade", cut out the new driveway extension to the garage (28 ft. wide X 30 ft long), relocate my current driveway, and because I was going to have 20 to 30 Ton or so of dirt left from the drive and building site I was going to re-contour my front lawn and hopefully solve a drainage problem. I was able to borrow a laser transit (I work at an engineering college), but you can rent them. Of course I already knew how to use it, but that can be learned in 20 minutes. I think they rented for around $60.00 a day at that time, but have come down considerably since. You can buy one at Sears for $200 to $300 and you will use it a lot more than you think.  

I have a property marker stone, probably granite, that was placed in the 1850's or earlier (my abstract shows this land was given to soldiers of the Civil War as payment for their services by the Federal Government) and hasn't moved since, so I used that a my "zero" point for every measurement. By setting the instrument to use this stone as a reference for everything I didn't have to worry about things changing.