RCM on Renting of working women hostel

The owner of the commercial building is not registered under GST.
He renovates the structure, adding 27 rooms with attached bathrooms.

Another person, a GST-registered individual, who owns a hotel business took the above building on rent to operate a working women's hostel.

Query:-
1. Does the GST-registered individual have to pay RCM on rent payments?
2. Is the Working Women's Hostel business GST exempt? 
3. Is it necessary for a GST-registered person to obtain new GST registration for a new hostel business? or continue to include the Turnover from the working women's hostel in the current GST Monthly Return.
4. if the Working women hostel business is exempt and RCM applies then how can utilize the input credit acquired through RCM