Legally
1) Release deed / Gift Deeed is required to be done from mother to you and brother to you.
2) I quoted Gift deed because stamp duty and registration fee for gift deed is very less in maharashtra below 1000. It should be duly registered
3) But there is one issue which too required to be considered A) CIDCO is lessor of whole navi mumbai 2) Society is leaseee 3) You are member of society as flat owner.
4) Under circumstances CIDCO rules and regulation is required to be studied and then only proper documents should be made and I think concent of CIDCO is required else they impose high penalty
5) This website can be useful for you (It is official website of CIDCO)
https://www.cidco.maharashtra.gov.in/ProM_actsregulation.aspx
6) Better visit CIDCO office once and try to get standard forms if available with them or zerox shop/nearby shop
7) Most imp. thing although I said zerox shop etc.
It will be better after collecting all documents you show to Advocate because such property transcation can create dispute in future if not done properly in good time.
I would suggest after doing preliminary servey for 1 or 2 days in CIDCO office then approach adv. doing such property transcation
Without proper consultant it is like taking heart medicine without consulting Cardiologist , and logically you can understand if some thing goes wrong what consequence can take place. Do properly with help of experience proffessional
