After my grandfather died, my grandmother was hell bent on staying in their home, even as her health declined and she really should have been in some sort of assisted living facility (and eventually a full medical facility). She didn't need the money. She was in her 80s, had few expenses and enough money to 6 figure inheritances to her 3 children. Another million dollars would have changed her life in almost no way.
That was the house where she had her final memories of her husband of more than 50 years. I can think of almost no motivation that would have gotten here out of that house. Because it was her home, and the money meant little when she had little time left anyway and was set financially.
Maybe you leave this poor old man alone, stop hounding him, and move forward. You've said you don't even need him to do this, so move ahead and respect his decision. You've asked the question, and he's answered. Checking back one more time as the process moves forward--"Hey Fred, 12 houses are selling, and if you join, the Smith's and Jones can sell too, bringing the total to 15. If not, the 12 of us are moving forward and an apartment building is going up where our houses are, so I just wanted to check one more time and make sure you haven't change your mind. No, you're staying. Okay cool. I wish you the best. Have a nice day." Beyond that, leave him alone. Your greed is causing you to consider blackmailing your neighbors, and strong arming an elderly man. WTF is wrong with you??
