I contracted my own house and used my litle JD 4100 for a bunch of stuff.
Hired an excavator to dig the main foundation - they stripped off the topsoil and put it to one "end" of the pile.
I did all the foundation drainage work myself - loaded about 30 yards of pea-gravel on top of corrogated poly drain pipe and then put filter mesh over that before the remainder of the back-filling.
We used a bituthane rubber membrane for water-proofing because it was the thickest, most durable thing I could apply myself without any special tools - just unroll, peel, and stick the 100' x 3' thick rolls of asphalt-coated rubber onto the concrete. In areas of the house where we felt drainage may be an issue, we also put in farbic-covered dimpled plastic stuff I can't remember the name of to drain everything down to the drains at the bottom. We used 1/4" siding insulation to cover the remainder of the bituthane to protect it during back-fill.
We then did all the back-filling ourselves. It took a while. Seemed quick at first for the walk-out side of the house near the pile where the foundaiton was only 54" deep, but by the time we got to the 9' deep side way around the other side of the house from the pile, it was a lot of trips back and forth from the pile.
We did not compact this backfill because I did not want to stress the still-curing concrete basement/foundation walls. After about two years of freeze-thaw, though, the deepest sections sank about 18". Before final grade and sod, we just made sure the slope was properly away from the house in these settled areas. We did not build anything structural over the back-fill.
The 4100 was great for loading in the sand fill on the inside of the house under the basement slab - just drove right in and was maneuverable enough even with lots of piers and structual walls in the way.
At one point during the rough grading process, the project was a bit behind, and we hired the excavator to come back with a large track-loader to move the bulk of the dirt to the right places arund the yard.
I did some of the final leveling and raking of debris with my 4100 and a landscape rake.
They also came back with the track-loader to cut the driveway into and through part of a slope. Hauled out about 6 loads of clay and replaced most of it with class-5 graded limestone.
The concrete guys had their own bob-cat to final level stuff under the flatwork, but my 4100 still did a bit of moving of crushed rock and such becaue it was handy in the tighter space inside the garage, for example.
The sod installers brough in their own bobcat with grading bar to spread the 6" of hauled-in black dirt we put under the sod in the front yard. Mostly because I didn't have time at the time.
The little 4100 was capable of doping almost anything we would have had to hire-in or rent a bobcat for.
Bottom line, its not clear we "saved" any money having the small CUT on-site. It was damned convenient, though and did save a heck of a lot of time on all the misc. things you always have to move around. If I had it to do over again, i would find a good used, rubber-tracked-skid-loader with a bucket, set of forks, and a mini-back-hoe thingy. I'd rent a tiller, trencher, grading bar, etc for it as needed.. I'd hire out all the big-excavator work. Then when the house was done, sell the track-loader and get a smaller cut for cutting grass, plowing snow and misc. landscaping.