I have rented several post hole diggers in the past: shovels, 2-man augers, etc., but nothing made the job as quick and easy as the pendulum post hole digger I rented here.
This tool has wheels and hooks to a trailer hitch to get it home, but don't let that intimidate you, it was manageable for 1 person to push and pull around their yard. I have a substantial slope in my yard and had to work in some fairly tight spaces.
I used this to auger out about 20 holes in 1 day for my fence--it worked well.
The other auger options might be a little cheaper (approx $60/day), but this is probably the easiest way for 1 man to do the job.
I would recommend the Tool Rental Facility at the Kanata HomeDepot and the staff at this location were helpful and friendly.
Address: 10 Frank Nighbor Pl, Kanata, ON K2T 1C4
Phone: (613) 271-7577