The first act of an estimator when about to figure on a set of plans is to provide himself with a schedule of materials likely to be used, so that nothing can be overlooked when taking off quantities. It goes without saying that some form of list must be used by an estimator when taking off quantities, and if he depends on making up such a list as he proceeds with his work he not only is sure to omit some important items that will cut down the contractor's profit, or cause him to lose money on the work, but the additional time required to make up a list for one big operation would more than pay for the printing of one thousand blanks. Full and complete estimating blanks may be purchased at small cost from publishers, or the plumbing contractor can make up a list applicable to his own locality and the conditions that there obtain. He should not attempt to do much estimating, however, without a list of some kind to check his calculation. Indeed, every known means should be employed to safeguard the estimate by various forms of checks. The plumbing for a large New York hotel was once awarded to a contractor who was well along with his work before he discovered that the soil pipe, fittings and calking lead for the work had been entirely overlooked. Such a state of affairs would have been impossible if an estimate blank had been used, for a glance would have shown the missing quantity.