Sub lease Deed

Dear Experts, Need support for the following -- Back ground. Planning to buy an apartment in Indirapuram, Ghaziabad (NCR) in resale from Mr x in a xyz Builder Project. Key points -- Ghaziabad Development Authority has given land for 90 years lease to Builder xyz Offer of possession of apartment was given to Mr x. (apartment is ready to move) The ownership of property in name of Mr x is by a Sub lease deed between the builder (Lease PARTY ONE) and Mr x (Sub lease PARTY TWO). This Sub lease deed is registered in Ghaziabad Sub Registrar Office. Queries -- Query 1>> Can Party TWO further sub lease to me i.e. transfer all property rights? The Sub lease deed between Builder and the Seller has the following clause -- “Subject to all applicable laws, rules and guidelines of the Authority/State Government the sub lessee shall be entitled to transfer the title of the said Flat/Dwelling Unit" I think with the above clause, the seller can transfer the property rights. However I have the following doubts 1. Will the permission to transfer be required from Ghaziabad Development Authority (as it’s the very first party who has leased the land to Builder?) 2. Will the permission to transfer be required from Housing Society? 3. Will the permission to mortgage (I have to take Bank Loan) be required from Ghaziabad Development Authority (as it’s the very first party who has leased the land to Builder and permission will also provide cover for –“ Subject to all applicable laws, rules and guidelines of the Authority/State Government” 4. Will the permission to transfer be required from Builder (the sub lease deed is already registered with GDA?) 5. Will the permission to mortgage (I have to take Bank Loan) be required from Builder (the sub lease deed is already registered with GDA) Will I be further able to sublease to PARTY FOUR in future? Regards