Complications in selling a jointly owned property

Hello, My question is regarding our ancestral property (house and land) spreading over 2 Kottah 11 Chataks owned in the name of my late grandmother Smt. Namita Mukherjee, mother to 6 sons and a daughter, my father being the eldest son. All the 7 heirs are named in the Mutation of the property that was done about 2 years ago at the local Municipality in North Kolkata. There has been no partition-deed done to the property, however, the heirs have lived in their own separate rooms under the same roof. Currently, only 1 of my uncles (heir), Mr. Jatan Mukherjee lives there with his family. There are only 4 rooms in the house, the 3 other vacant rooms are locked by the other uncles who used to live there. My father (and his family) and the other 4 uncles and their families have been living elsewhere for years now, due to lack of space in that property. The other heir, my Aunt is married. Now, the present condition of this old house is quite worn out and since the place is quite small for 7 heirs, 6 of the heirs wish to sell this property and have their equal shares of the money post sale. However, the 1 heir, Mr. Jatan Mukherjee who's currently living there with his family is opposed to this. He is rather of the opinion that the partition-deed be done on the property, so that he can have his own room renovated with the help of the local Municipality. But the others don't want this as this would only complicate things. The other 3 heirs would then claim for the 3 remaining rooms, and the rest of the 3 heirs including my father wouldn't have any space left to claim. So, in a nutshell, 6 of the 7 heirs want to have the property sold and 1 wishes to partition it and keep his own portion, which from the outset sounds simple, but would actually be very complicative. Can a lawyer advise as to how this can be approached for a resolution ? Thanks. Tamal Mukherjee.