Ferroelectricity continues to fascinate materials science researchers, as new ferroelectric hybrid materials and unique aspects of the phenomenon continue to be discovered, highlighting its potential for innovative technological applications. In this study, a novel inorganic-organic hybrid material consisting of 3-quinuclidinone cations and a tetrachlorocobaltate(II) anion is synthesized using a green, solvent-free mechanochemical approach. Two forms of this compound (anhydrous and hydrate) can be prepared depending on the reactants used. These two forms can be converted into each other under humid or dry conditions. In addition to humidity-induced transformations, the material also exhibits several phase transitions triggered by temperature changes. Ferroelectric phases have been observed for the anhydrous phase at low, room and high temperatures. The occurrence of multiple transformations reflects the soft crystal packing of the 3-quinuclidinone cations and the tetrachlorocobaltate(II) anion, which is controlled by non-covalent interactions. The structural flexibility of this material makes it ideal for deposition on substrates achieved by the dip-coating method. The resulting metal–organic thin films grow in a specific crystal orientation on Si(100) and ITO-coated glass substrates and yield uniform and crystalline films. According to remanent polarization measurements, these films show stable ferroelectric switching under ambient conditions.