I just checked rates for a few SPG hotels around Delhi. The 4P Delhi Airport correctly charges 9% GST onlyon a base rate of INR 5,700 and the Westin Gurgaon correctly charges 28% GST only on a base rate of INR 8,100.
Contrary to this, the Park New Delhi charges 15% Luxury Tax on a Rack Rate of Rs 5,999 + "Krishi Kalyan" tax of 0.3%
All these were for stays in October!
PS. What happens to F&B charges - are these matched to the GST rates applicable to the rooms at the property? If so, what happens if the hotel has some rooms below the INR 7,500 slab and other rooms above that level? So what rate do you pay for a cup of coffee at the restaurant?