I recently discovered the passing of a great aviation AND Mooney enthusast, Fred Quarles. Fred Quarles purchased the M-18 type certificate and made the plane available to the public in the form of a homebuilt in the 1970's (Mooney Mite M-18X). It appears that the type certificate is available for sale by daughter Ellen Michelle Quarles via a post in the Mooney Mite Owners Forum of MooneySpace.