Building construction supervision; providing construction information; construction of government, educational, commercial, industrial, residential and public buildings, hotels, laboratories, sports arenas, medical institutions, roadways and bridges; factory construction; warehouse construction and repair; masonry; demolition of buildings; installation of building insulation; damp-proofing of buildings; bricklaying; road paving; asphalting; pipeline construction and maintenance; pumicing; harbour construction; pier breakwater building; underwater repair; scaffolding erection; rental of construction equipment; rental of bulldozers; rental of excavators; rental of cleaning machines; drilling of wells; installation and maintenance of seats, stages, playing surfaces, running machines, torso rotation machines, horizontal bars, parallel bars, rowing machines, and kin-riding machines at entertainment and sports venues; mining extraction; quarrying services; upholstering; upholstery repair; paper hanging; painting, interior and exterior; painting and repair of signs; cleaning of exterior building surfaces; cleaning of interior building surfaces; window cleaning; installation of heating systems; boiler cleaning and repair; irrigation devices installation and repair; electric appliance installation and repair; installation and repair of air-conditioning apparatus; installation and repair of freezing apparatus; office machines and equipment installation, maintenance and repair; kitchen equipment installation; machinery installation, maintenance and repair; installation, maintenance and repair of computer hardware; interference suppression in electrical apparatus; installation and maintenance of medical devices; installation and maintenance of hand basins, spigots and flush toilets; installation and maintenance of lights at sports and entertainment venues and public buildings; vehicle service stations for refueling and maintenance; strong-room maintenance and repair; rustproofing; re-tinning; furniture restoration; furniture maintenance; pump repair; elevator installation and repair; telephone installation and repair; burglar alarm installation and repair; fire alarm installation and repair