In resent years has been increasing interest for application of probabilistic methods, in particular queueing theory for estimation of activities of managing companies of residential buildings. Maintenance of residential buildings is a set of measures that ensure the highest reliability of all elements and systems of a building. The main element of the technical operation of residential buildings is a system of scheduled prophylactic inspections and repairs. However even with its rational organization, there is always a positive probability of failure of building elements, which depends not only on the aging factors of the structure. The goal of the managing company is, on the one hand, to prevent the formation of a too long queue of emergency calls, and on the other, to complete all planned prophylactic maintenance work. As a mathematical model we consider a single-server queue with vacations and close-down periods. The service team can start a scheduled preventive repair only when all request for sudden mailfunctions are satisfied. This period we call vacation. There is a close-down period before vacation. This time period is required for preparation and organization of the prophylactic and inspection work. Based on the methods of the queuing theory, the system’s characteristics that determine the quality of its work, as well as the boundaries of the change of parameters at which the system copes with the work from the standpoint of a particular criterion are defined.