Since it's his brother, he can leave the house to him in his will! (it would be a surprise and I don't see why he wouldn't leave the house to his brother) I simply cannot see Charlie leaving the house to Alan. He's just too selfish. Honestly, if they do kill him I could see him leaving the house to Jenny McCarthy's character (if they're still together I haven't seen a new episode in a long time) before he leaves it to Alan. She'll either become Alan's landlord and be a total pest or she'll throw him out. Alan will either move in with his mom or move to a junky apartment surrounded by wacky neighbors.
That's how I'd do it anyway. Alan was once compared to Job w/ God pushing him around for fun. Things can't work out for Alan unless it's the series finale. If they plan on keeping the show running they have to keep finding ways to push him around. Getting the house in Charlie's will would be too close to things going in his favor.
"All our dreams can come true -- if we have the courage to pursue them." -- Walt Disney
We must have different Gods. My God said "do to others what you would have them do to you". Your God seems to have said "My Way or the Highway".