It’s really not difficult. The government at the time, who were footing the bill, stated it was costing £8M per day to house the flood of people arriving illegally. That figure is now £9M per day with increases in numbers since the original figure was released. Times that by 365 gives you £3.2Billion per year.
The number of genuine asylum seekers within that figure is SO minimal as to be insignificant.
That is just the financial cost of housing them. It doesn’t include the monetary handouts they are being given, the new mobile phones they are given upon arrival, the drain on our health and education services and the cost to society with the untold crimes they are already responsible for.