The 68 King William Street asset was bought for an undisclosed sum. : Ares Management’s real estate arm has teamed up with London property investor Black Mountain Partners to buy an 11-storey office and retail building. Funds managed by Ares Real Estate Group and Black Mountain have acquired 68 King William Street, London EC4 for an undisclosed sum, the companies said in a joint statement. The 97,538sqft 68 King William Street asset is currently home to a diverse mix of office, food and beverage, and retail tenants.