(1) (a) Who owns the property known as the Wingfield Military Base bordered by Voortrekker Road, Vanguard Drive, N1 and 18 Kensington and (b) what is it currently being used for; (2) what plans does his department have for the future development of the property; (3) (a) who is responsible for the upkeep and maintenance of the property and (b) on which date was maintenance work last undertaken?