Can my dad sell the property of my deceased mom name but contructed by my dad own cost

How 

Bcoz  I know  thekka tenancy  rules  that imply structure  made by the person  by his own cost  and residing more than 20yrs then that  person  will be thekka tenant of  government of  West brngal 

I want to know  that bcoz in  kmc  my decased mom and mama name register 

But  structure made by my dad by his own cost  

Mother died 25yrs ago 

I hv  1 more  abnormal Bro and married sister they stay  together 

I stay with my dad here 

If my dad is owner  of structure  then how shall  I mk legal paper 

Bcoz my sister  objecting saying  this mother property  

But  dad want to give me  

So  want to know  he  had power  to give me  by minusing other 2 hier 

Or 

If u saying it's mom property bcoz the  bharstiya was my  mom grandmother she died issueless  in corporation  her name available 

By her only my mom and my mama  r inhrrtited  

Want to clear this  if  owner is West brngal government according  to thrkka tenancy  then person  who invest in structure  he is the actual owner or not 

Please post simple facts.

Just tell me my dad had contructed 1floor in theka land which is  joint property of my  deceased mom + my mom brother

Tell me what is my dad power? 

He contruct 1floor residing from 35yrs 

Can he is sole owner of that structure 

Or 

The theka land owner  who issue  rent   to tenant  (my mom+her Bro)  had power to sell 

I am saying this bcoz sm1 said me the west bengal government is the landlord of this land other who own this land is called bharatiyas so if I want to mk legal paper of my house then on Wat base I  want to clear  that in this  structure  contruct by my dad  who  can sell?

1, my deceased mom + her brother  who own  land  name in kmc 

2.my dad power  in that  structure  I asking only   which is under us. 

The typical local terms, revenue codes/rules/laws are involved and LOCAL counsel well versed with such matters can understand better and guide and help.

Approach a very able senior LOCAL counsel of unshakable repute and integrity specializing in revenue/civil matters and having successful track record………………and worth his/her salt..

Generically speaking; tenancy/theka is not ownership. 

If you wish you may approach LCI Experts from your state e.g;

Mr. Devajyoti Barman…

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