GST exemption for development rights and long term lease provides calculation and reverse charge on unsold units with capped tax liabilities. Amendments add entries 41A and 41B exempting GST on transfer of development rights/FSI and on upfront long term lease amounts for construction of residential apartments, with the exemption apportioned by carpet area. Promoters must pay tax on the proportion attributable to unsold residential apartments on issuance of completion certificate or first occupation under reverse charge, subject to caps; valuation of transferred rights and unsold apartments is deemed to be the value of similar apartments charged by the promoter nearest the relevant date.