[Rinty]

Jerry;

I would steer clear of buying any of grandpa's property, because if he gets more agitated over time, he may start directing his energy your way, regardless of how carefully you documented the transaction. Also, he may end up associating you with his problems, directly, or indirectly via your ex, with whom he also has issues.

As an attorney, I've seen similar family property transactions end up very badly.

Perhaps, when grandpa eventually passes, there will be some other momentos left, by which your son can remember him.

Good luck.