Abstract: A method and system for offering customer information service to specific customers timely over communication network according to the changes in daily living circumstances of the customers staying or living in dwelling house, office building or the like and a multi-functional communication terminal unit of the network-adapted type are disclosed. According to which, monitoring information on living facilities and equipment used in dwelling houses, office buildings or the like is constantly watched by a dwelling management server and the dwelling management server automatically sends the monitoring information to a service server equipped on a communication network immediately when there occurs a change in monitoring information and at specific time intervals when there is no change in monitoring information.