Gst rate on electrician, plumbing,cleaning and repairing work

Hello All One of my Client provides different kinds of services like architech, cleaning of offices,plumbering services,civil structure,repairing of AC/Tv/wishing machine and other related work contract services and they have incorporated a pvt ltd company and registered for service tax however they have not provided any services yet as business has not been started yet. My Question is How would we migrate to GST we dont have any user id or password for Service tax ?will it a migration or fresh registration in Gst? and what is the Gst rate of above mention different kind of services? what is rate of Gst on work contract services? Thanx in Advance