Section 14(1)(c) in The Goa, Daman and Diu Land Revenue (Conversion of use of land and non-agricultural assessment) Rules, 1969
(c)in the case of a sale of a plot with superstructure where such plot is not assessed to land revenue or rent, an amount equal to the difference between the amount of the sale price thereof and amount of the market value of only the superstructure on the date of the sale shall be the full market value;