I think Dwight is right though, it looks like a worthwhile project for the right person. Finding the right person might be tough. Someone with the skills to do the bulk of the work themselves that wants an Avanti would be the ticket. I think it’s pretty tough these days to buy any classic with the thought of restoring it and then making money on it.
Sad story, guess whoever got the car from your grandmother wasn’t looking out for her. Mike