37 Real estate building construction; cleaning of real estate property; renovation of buildings; advisory services relating to rebuilding of real estate buildings; servicing, maintenance, and repair of building technology installations and devices, namely, air conditioning systems, heating systems, sanitary installations, electrical devices, HVAC systems, smoke and heat extraction systems, burglar alarm systems, elevator systems, door installations, and gate installations; building cleaning, building repair, building restoration, building maintenance, building reconstruction, building renovation, and consultancy relating to the aforesaid services; janitorial services for buildings, patios, car parks, garages, outdoor facilities, playgrounds and access roads; cleaning of elevator shafts; cleaning of escalators; cleaning of doormat and cleaning mats; cleaning of facades; window cleaning