GST on property delivered by builder as part of JDA - Value of Supply

Facts:

1. JDA registered in Aug 2017. 6 floor commercial property construction.
2. Developer completed construction in Dec 2021.
3. Occupancy certificate received in Jan 2022.
4. Developer issued allotment letter in March 2022.

Valuation:

1. Valuation of the constructed area as per the local registration office is Rs.2000 per sq ft.
2. But developer sold his share of the ground floor of the commercial Constuction to his buyers for Rs.8000. Their registration value to their  is Rs.8000 per sq ft.
3. Landlords did not sell any part of their share 

Question(s):

The value of the constructed area differs from floor to floor in a commercial construction. If ground floor is Rs.8000 per sq ft the the price for each subsequence floor is less than Rs.8000

Ground Floor: Rs.8000 per sqft

1st Floor: Rs.7000 per sqft

2nd Floor: Rs.6000 per sqft

3rd floor : Rs.5000 per sqft

4th floor: Rs.4000 per sqft

5th floor: Rs.3000 per sqft

6th floor: Rs.2000 per sqft

1. In such a scenario how will the value of the property be calculated for levy of GST for landlords ?
2. Is there a possibility or is it as per GST law if the GST dept values the entire 6 floors square footage at Rs.8000 per sq ft ?
3. How will the GST dept determine the value of square footage on each floor for landlords ?
4. Are there any GST tribunal decisions on this subject matter ?