“The application of the deferment rate of 5% for flats and 4.75% for houses that we have found to be generally applicable will need to be considered in relation to the facts of each individual case. Before applying a rate that is different from this, however, a valuer or an LVT should be satisfied that there are particular features that fall outside the matters that are reflected in the vacant possession value of the house or flat or in the deferment rate itself and can be shown to make a departure from the rate appropriate.”