On September 1, 1970, Buchanan Airport Hangar Company entered into a 30-year lease with Contra Costa County for the construction of seventy-five (75) hangars and eighteen (18) aircraft shelters/shade hangars at Buchanan Field Airport. In 1977 Buchanan Airport Hangar Company amended their lease to allow for the construction of another 30-year lease with Contra Costa County for the construction of seventeen (17) additional hangars. Buchanan Airport Hangar Company was responsible for the maintenance and property management of the property during the lease period.
On September 1, 2000, the ninety-three (93) t- and shade hangars at Buchanan Field reverted to the County ownership pursuant to the terms of the above lease.
On November 14, 2006, the Contra Costa County Board of Supervisors approved the form of the T-Hangar and Shade Hangar Rental Agreement for use with renting the County's t-hangars, shade hangars, medium hangars, and executive hangars at Buchanan Field Airport.
On February 16, 2007, the additional seventeen (17) hangars at Buchanan Field reverted back to the County pursuant to the above referenced lease. This row included six (6) large hangars which were not covered by the approved T-Hangar and Shade Hangar Rental Agreement.
On February 23, 2007, Contra Costa County Board of Supervisors approved the new Large Hangar Rental Agreement for use with the large East Ramp Hangars.
On January 16, 2009, Contra Costa County Board of Supervisors approved an amendment to the T-Hangar and Shade Hangar Rental Agreement and the Large Hangar Rental Agreement (combined "Hangar Rental Agreements") which removed the Aircraft Physical Damage Insurance requirement. The Hangar Rental Agreements are the current forms in use for rental of all the County hangars at Buchanan Field Airport.