In this step the Estimator must complete the following task:

Calculate man-hours

Calculation of direct man-hours

All the steps to make a quotation are equally important, but the calculation of direct man-hours needs:
An excellent capacity of analysis and study of the group of estimators that executes the offer.
Access to a reliable database on the number of man-hours or fraction of them that are normally consumed in a standard work situation when executing a Work activity.
Specialist technical support.

Man-hours

This total of man-hours consumed is only valid if the Project is executed under conditions similar to those existing when the performance measurements were made.
As each Project is different from another, the total hours arising from the mathematical calculation must be adjusted with factors that take into account the influence of the particular conditions of each Project

To abbreviate the above, we have:
The estimators must have reliable information about the consumption of man-hours or a fraction of them that a team uses to carry out each activity.
The estimators must have complete knowledge of the conditions in which each Project is developed and of which factors affect the total hours calculated mathematically in the previous step.

In order to accomplish this task, the estimator needs the drawings, the computing of materials, the Tables with performance records, the adjustments to be applied to these performances and the permanent technical support of the specialists.
After estimating the direct man-hours required for each specialty and with the data of the construction period, the number of workers to be employed is obtained.
In general, the Builders have permanently updated the cost of the man-hour of each assistant, half official and official dressed (that is to say with work clothes and the elements of Security) and with his box of tools for each specialty.