Assume Quirk( Complete Scoundrel, p. 85)
[Interaction, Skill Trick]
You can perfectly imitate a small habit or idiosyncrasy of a person you impersonate in order to throw off suspicion.
Disguise 5 ranks,
When impersonating a particular individual, you can eliminate the normal Spot bonus granted to a viewer familiar with that individual (PH 73). The effect extends to all viewers.
Using this trick requires no special action, but you can maintain the deception for only 1 hour per day.