In considering the running expenses and cost of maintenance, the foregoing discussion of construction, equipment and finish is the most material point. In addition to this, the character of the building must be considered, the necessary service to be maintained, the pay roll, etc. Unnecessary elevators add to the cost of maintenance and unnecessary employees do likewise. Where a building is so built and finished as to be classed as a poor building and badly equipped, it may be safely estimated that the cost of maintenance will be high. The character of the neighborhood, the character of the building itself, and the character of the tenants will also influence the cost of maintenance. Certain classes of tenants depreciate the value of property rapidly by their general ill-use of their apartments, whereas a higher class property, with refined tenants, can be maintained for a much longer period at a much less expense pro rata.