The value of structure is taken as 4,70,000
As per government law, 5% of land value and 6% of construction value can be taken as return in one year.
Based on the above figure, the monthly rent of the building should be determined.
4,00,000 + 4,70,000 = 8,70,000/4017 = 216.58 months
216.58/12 = 18 years.