Is the bug corrected yet? I got the quest to kill him from the Dark Brotherhood, and having it active drives me a little crazy, I'm going to get the DLC's soon after I finish the main storyline, but I want to get all of the achievements. I'd like to kill him, and collect the money but I read that if I do that I'll never be able to purchase a plot of land I need for a couple achievements. So if anyone know's if this has been corrected or is still bug please let me know.
Is it really a bug that killing a Jarls Housecarl makes him dislike you? Anyway just get the DLC and Lakeview first then murder him, or murder him now and then do the DLC with a new character.
To get all the trophies i used five diffrent characters one just to play how i want to one for the Assassins and Thieves quests then one to get all the Daedric Artifact and also another for the Companions and the Civil War (as a bug broke the war). Then when the DLC (finally) came out i made another new character for the new DLC trophies.
The bug only really occurs if your caught doing it, as with most of the 'bad blood' you get from killing anyone. If you're discrete and stealthy in your kill, it really doesn't affect anything. Their relationship will remain unchanged with you, as they were none-the-wiser.