In this discussion between Jeff Givens and Jeff Spencer, the guys talk about setting your man hours in your job bids. As Spencer explains, you do not want to try to bid a job with the exact number of hours you think the job will take because you leave yourself no wiggle room for mistakes or to account for job conditions beyond your control. They discuss analyzing a project afterwards to see what went wrong in a project to cause it to run over on man hours.
They also discuss the dangers of getting too close to a donkey!
From ProfitDig - easy, low cost construction job bidding, costing and reporting.