+1what Eddie said. He pretty much covered all the bases. After digging (renovating) the pond myself and with a friend, he's spot on.
I needed to move the remainder of the dirt from the renovation, and dig some out of the pond that washed in, so I rented a wheeled backhoe. They dropped off a Komatsu, but after a day they replaced it with a JD 310SJ (the Komatsu had a leaking heater core). The JD had 25 hours on it when I climbed in it, 1 1/3 yd bucket on the front and they put a 24" bucket on the back. The JD uses about 1/2 of the fuel that the Komatsu did, and it moved faster because of being able to shift gears on the fly. I thought it was a pretty good deal @ $1800/month. They allow 176 hours/month and I'm hard pressed to get that many hours on it with having to move dirt to my parents house that is 8 miles away (via single axle KW dump truck). I think I moved close to 300 yds there in 4 long days by myself. (yeah, the loads were a wee bit heavy
)
Don't forget if you rent, and the weather turns crappy, you'll be sitting because the dirt will be too sloppy to work.
4-wheel drive really helps in the softer stuff when you're moving dirt with the front bucket, but even with 4-wheel drive, you can get stuck and will need to use the backhoe to pull yourself out. You can find unseen things under ground as well - I broke thru the lid of an abandoned septic tank and almost tipped it over. I had no idea that it was there by the stable!
While you can do a lot of work with one, for final grading it is much easier with a dozer. Anything that has a suspension on it makes it more difficult. When you go to cut, the bucket loads the suspension and it starts to cut deeper. You constantly need to adjust the depth of the bucket to keep any cut areas flat. If the tires slip and dig in, that changes the depth as well. With a dozer, there isn't any suspension and that's what makes it easier.
I'm just finishing up the property now, and this wet Spring is killin' me! I'v had a finish dozer scheduled to come over and hit the area around the pond for over a month now and every couple of days we get hit with another batch of rain.
A friend has a Cat ASV 1480. While this can move and pack a lot of dirt quickly with a skilled operator it is VERY high maintenance. He's constantly fixing the undercarriage or something else on it. But, he was able to move/place/pack dirt that was being fed to him my a tri-axle dump truck and a single axle dump truck as fast as we could bring the dirt from the pond, which was 200 Yds away. There was 4 of us that day, one in the excavator, one in each dump truck and one in the ASV. He was able to keep up, but just barely.
IIRC, Otto said that the quickest way to move dirt less than 50 Yds was a dozer, any further than that and the pan scraper gets the nod.
