A deep clean is the one we price by the hour, because until we have seen a place we would only be guessing.
It covers what a weekly clean does not: inside the oven and the fridge, behind the appliances, under the beds, the tops of cupboards, the fans, the grilles, the window tracks, the grout and the drains. On a two bedroom flat it is usually six to eight hours with a team of three.
Most people book one before Ramadan, before guests arrive, or once a year in a home we clean weekly anyway. It is also the honest first step in a place that has not been cleaned properly for a while, and we would rather do it once than pretend a three hour visit can.