The right tool makes any job easy
I used this Hydraulic Auger for my digging (see picture on left). I needed to dig 14 12" wide holes 48" deep!! There was no way I would've ever tackled this kind of digging without a machine. I used this machine for digging 40 fence post holes a few years ago and it worked so well that I wasn't the least bit concerned about having to dig my deck's post holes. This thing ripped right through the ground and I had all holes dug in about 3 hours.
I used a 3 person system. One person operated the auger, the second and third cleared out the loose dirt in the hole to prevent auguer from bogging down.
If you ever need to dig (in an area that doesn't have a lot of rocks of course) then use this thing! It cost me $100 for the day....WORTH EVERY PENNY!
The results: