Although the tank house (or water tower) is not original to the property, it sits on the original wood beam foundation and is the exact size of the original, about 16 square feet. Remnants of the southeast corner of the original mudsill foundation remain carefully in place. Fragments of a marble ground floor were also discovered. The current tank house was donated by a family from Van Nuys and moved onto the property. The water tank over the tank house is the original tank from the Calabasas School, a one-room Victorian structure built in 1890. The upstairs bunkhouse served as an additional bedroom for ranch hands or visitors needing overnight lodging.
The 19th century wine vats inside the ground story room were donated by Mission San Fernando.