Where is the perfect place to kill a person in oblivion?

Question

im trying to get access to the dark brotherhood, but there are strings attached like killing someone im in a guild with, too many guards around, or anything. its freaking pissing me off. help!!

Answer 1

I agree with Civil Av8r

Answer 2

Kill someone in their house.  Make sure it isn't anyone important to another storyline.

Answer 3

Break into their house, sneak up to their bedside, and assassinate them in their sleep. Be sure you're in sneak mode, so that you'll get the damage multiplier. If done right, the guards won't catch you, and it is pretty fast.