Given the government's history of failed and overbudget IT projects (https://en.wikipedia.org/wiki/List_of_failed_and_overbudget_custom_software_projects https:

Given the government's history of failed and overbudget IT projects (https://en.wikipedia.org/wiki/List_of_failed_and_overbudget_custom_software_projects https://en.wikipedia.org/wiki/List_of_failed_and_overbudget_...), probably billions of pounds for something that half works.