Section 12(1)(b) in The West Bengal Non-Agricultural Tenancy Act, 1949
(b)in determining the amount of enhancement the Court shall have regard to,-(i)the increase in the value of the non-agricultural land caused or likely to be caused by the improvement,(ii)the cost of the improvement,(iii)the expenditure (if any), required for utilising the improvement, and(iv)the existing rent and the ability of the non-agricultural land to bear a higher rent.