What method is best for making post holes. I have about a hundred holes and was thinking about renting an auger for my front loader or backhoe. If I do does anyone know if I can drill out all the holes first? (Renting for a day or two). Does that work? Should I do one post at a time? I am using 4X4 treated posts. What size auger should I rent or is a manual post hole digger just as good? Thanks for your help.