S. 23: Income from house property – Annual value -Vacancy allowance -Construction business- Some flats constructed by assessee were not let out during year -Properties held as stock-in-trade were not let out for any previous years, vacancy allowance is not available-Liable to pay tax on the sum for which the property might reasonably be expected to let from year to year under S. 23(1)(a) of the Act. [ S. 22,23(1)(a), 23(1)(c) ]