Whether it is legal to open shops on father's invested property

my grandfather has our bungalow land in his name..but construction of 2 floors of this same bungalow was paid by my father 90% and other uncle paid only 10%..we live on 2nd floor..this uncle lives on 1st floor..my grandfather lives on ground floor alone.since 1 year..my grandfather lives on 2nd floor with us..due to illness and loneliness..uncle does not pay any maintenance or regukar expenses to our grandfather since 50 years..our grandfather wishes to allow us to open shops on ground floor of bungalow..since it is road facing..can he allow us make shops legally? Can my uncle interfere in it? Because my uncle paid 10% in construction of bungalow?