I used to know a guy who befriended a professor at his university, and when that professor died he left everything to the guy, guy became almost a millionaire overnight. It does happen but it won't with Hoarderman. When Hoarderman dies, if he does leave anything to Jimmy, it's a rotten, decrepit house filled with garbage. Cleaning everything out is going to offset the value from whatever treasure is actually buried there.
I half expect Hoarderman to die, leave nothing to Jimmy (at least not explicitly), and Jimmy spergs out thinking he's owed everything.