Now, it is myself (grandson), my sister (grand daughter) and my mother (daughter in law) and two married daughters of my grand father who are alive
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Go step by step
First update land records , as per Hindu Succession Act ( I presume this is personal law applicable to you )
Then get measurement of plot done
Then Update all municiapl or local govt records
Get certified copy of Structue including Occupying Certificatre and Plan from Local Govt.
This is required and till you complete tell your aunties I am doing formalities let every thing become clear so necessary steps can be taken for doing transaction. This way you get time.
Rember whatever I told this are necessity for maintaing land and structure. So make all files properly regarding this property and maintain it , It will take time may be 6-7 months and you politely say doing work and get time.
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When all is over you shoud accept fact this aunties and their children in future are going to trouble you legally 100% . So try to get some housing loan etc. and pay them something and send them away. and make whole property on your name (Since you are paying so i prefer transcation should be only on your name not your sister or mother name)
This is compromising with them telling see I am loan so you also have to comrpromise. and Bank require all papers in order
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After this things don't go favourable then legal step will be
1) Filling suit for acquiring anchestor property to determine value of structure and land. You should file suit claiming there is valuation dispute
2) In this suit you should either calculate and come to conclusion or just delay the proceeding . Advocate know to delay the case , but delay that carefully without getting dismissed from non apperance etc. So you are not paying property is in dispute and age ka agge dekhenge
3) They may move partition suit so you should be ready for it too and delay the proceeding
4) Last but not least compromise some thing with them . See Girls have right you can not supress right rather situation is that you are staying in house which is owned by your aunty and thus legally under her oibligation this is new fact due to Succession Law. Even your mother is staying in house which is owned by your aunty. In that case if you diplomatically don't settle your children will stay in house with whom he does not have good relationship so eventually you and your family is without house bitter but reality with some wrong emotions attach to house which is owned by some one else . Bitter but this is not your problem this is national problem . When girls get right in property it has created situation that daughter in law is staying in house owned by her sister in law . Such complexity is result of equality policy between boy and girl in succession . Now only option left is that every generation separation takes place of property legally else , you never know due to compolex succession law your son stays in house owned by totally stranger or strange person because your aunt is absolute owner of property she can will the property or sell the property or gift the property even to stranger and except emmotionally fighting with her nothing can be done .
Few months back I was wondering about situation if family division of assets not taken in every generation you never know your son is forced to stay in house which is owned by total stranger due sucession law and he can kick your son out. Truth but bitter