An important part of this policy was the designation of much of Westminster's council housing for commercial sale, rather than re-letting when the properties became vacant. The designated housing was concentrated in those wards most likely to change hands to Labour in the elections. Much of this designated housing lay vacant for months or even years before it could be sold. To prevent its occupation by squatters or drug dealers, these flats were fitted with security doors provided by the company Sitex at a cost to local tax payers of £50 per week per door.