Vampire: The Masquerade - Coteries of New York (UP)

*MISSABLE* (See Enchanted To Meet You above for more important information regarding this.)

This trophy is fairly easy, and you'll likely get it on your own if you're not playing too aggressively. To get this, you should help D'Angelo as much as you possibly can, and, in addition, when the two of you confront him, don't be hostile to Robert. When the option presents itself, chuck a small rock. Do not ring the doorbell.

The only way to fail this quest is to be rude to him and to refuse to help his investigation, be unnecessarily loud and draw attention, and/or being rude/hostile to Robert. It's hard to fail these if you're not purposefully acting like an aggressive lunatic, so you should be fine.