You need shelter for the aircraft (hangars), storage for fuel and other consumables (ammunition, film/data storage, etc), repair facilities and their associated storage requirements, facilities for the personnel assigned to the base (at the very least breakrooms and bathrooms, not to mention workspaces and command/control facilities, and probably housing as well-which comes with its own needs), a control tower with both visual and equipment navigation, and of course security personnel and the related infrastructure needed to secure and patrol a secure-access facility. I don't think 10 grand and an old KMart would be able to supply all of those things.