Flat possession without completion certificate

Builders in NOIDA are offering provisional possession of flats without completion certificate from NOIDA because of ban on issue of completion certificate due to NGT issue . in this case sub lease deed cannot be executed with NOIDA.my builder is also planning to do same to get final balance payment. people in other society in the locality have started moving in their flats by making balance payment and without sub lease deed.What should I do on receipt of possession letter. CLAUSE 19(HOLDING CHARGES) OF MY AGREEMENT MENTIONS "THAT NO POSSESSION OF THE FLAT SHALL BE HANDED OVER UNLESS THE SUB LEASE DEED OF THE SAME HAS BEEN DULY EXECUTED BETWEEN NOIDA, THE COMPANY AND THE ALLOTTEE" If I go ahead with payment of balance amount the builder will get his balance payment and also avert further late penalty and will also start levying maintenance charge @Rs 2.25 psf +service tax. will I be able to rent out the flat not registered in my name?