Gift deed

My father was the registered owner of his self acquired property and died about 25 years back intestate leaving behind his spouse, two daughters and one Son. Soon after his death, the Khata of the property was got changed in the name of my Mother without the knowledge or consent of her Son. The said property is still remains to be undivided. My mother is of 80 years of age and still living in the said property. Now one of my sister has put up a proposal for Gift deeding the entire property to be executed by my mother in favour of her 03 siblings bequeathing the entire property equally among three of us. The condition put forth is that; 1) As the property is a self acquired property of my Father, there is a thinking to preserve it for the use of 03 of his siblings for constructing a Building over the property. In the event, any one of the sibling is not interested, then He/She would get share determined by Guidance value (not Market value) fixed by the Government for registration of property. 2) In the event of all her children decided to sell the entire property to a third person, then all will share the sale proceedings equally at Market rates. My questions are: 1) Can my mother execute gift deed for entire property including her share legally as she happens to be one amongst us as far as share in the property is concerned. 2) Does 1st condition sounds good in terms of providing justice to other two as far as value of the property is considered if sold at Market value.