Society Formation

I am a single woman. In my building (I along with my two other siblings plus my late mother are co-owners of this place) there are 7 floors having 2 flats on each floor. (Total 14 flats) We have 4 floors (8 Flats) with us and the other person who paid for the construction this building (on paper though I am the builder and he is the architect) has occupation of 3 floors (6 flats) which are utilized by he himself and his other 3 family members. It is important to state that he and his family paid for the construction of this building against which he was allotted 3 floors(6flats) as per our MoU. However after managing to get the CC Certificate, he has stopped paying for the balance work. Despite of this he wants to create the society so that completion of the balance work will become the responsibility of the society. We are objecting to the formation of the society due to this reason. The entire maintenances is borne by me. Question : Can he and his family force us to form the Society? Which law can protect us?