Comment by bluGill

I don't think he can get the required certifications and charge a reasonable price for this plane. There are not enough people interested in a personal airplane at any price to support the costs to bring a new one in the air. You can rebuild all current airplane's (most built before 1980) for much less than the costs to certify a modern replacement, and only then can you start asking what it costs to build that replacement. Which is why we rebuild old airplanes all the time - it is wouldn't pass modern regulations but since it already exists it is certified.