Need understanding regarding Following:

At present we do sales - New lift sale/Modernization/Repair/Maintenance in. Presently All  are under works contract.

Post GST composite works contract are going to be covered under works contract service & will be charged @ 18%. Need to understand exact tax position with avaialbility of  ITC on it.

Further under the rate chart  under chapter 84 under point no .13, on Elevator, GST rate is given as 28%. 

Needs to understahd how exactly we should go about the two rates 28% & 18%