How Little We Know

 is a quest in Fallout: New Vegas.

Detailed walkthrough
This quest is activated once Bye Bye Love is complete. Inside the main entrance to the Gomorrah, talk to receptionist on your left. Ask her about "the outstanding balance" on information to find out what's been going on in Gomorrah. She will tell you to find Cachino, a low level lieutenant, and ask him about suspicious Omerta activities. Another way to start this quest is as part of For the Republic, Part 2, you will be asked to get some information regarding the Omertas by Colonel Moore. She will then tell the PC to talk to Liza O'Malley to start this quest.

you need to find proof of Cachino's work he's been doing on the side that the Omertas don't know about to get him to talk. There is a journal in his desk in his room with evidence and another on his person that can be pick pocketed, his desk will be the one directly to your left as soon as you walk in his room. You can get the key from the receptionist. Once you return to Cachino and tell him you have his journal, he will offer you 100 caps to get the journal back, (or more if you have a high enough barter skill) He tells you about two people in the club that were brought in by the bosses as part of their plans, but doesnt know much about it, he tells you to talk to Clanden and Troike about specifics.

Clanden will not give you any clues or talk with you about what he does at all, even if you mention cachino sent you. If you go back and speak to Cachino, he'll mention he did some asking around and the bosses plans would be screwed if Clanden wasnt around, so he asks you to kill Clanden discreetly. Clanden will turn hostile as soon as he sees you draw a gun. Once you take care of him, report back to Cachino.

When you speak to Troike, start asking about the dead hooker, if you have the Medicine skill at 30 you can say that the story about him blacking out doesn't add up. The player can either find evidence that there was foul play by investigating the dead hooker in a hotel room, or by looking for other evidence (such as a blackmail note in big sal's office safe that proves the bosses set Troike up). Alternatively, you can talk to Big Sal and convince him to free Troike from his contract with a high enough speech or barter skill, this allows troike to be freed without having to investigate the dead hooker incident or find any evidence.

Once Troike has been freed of his contract, he will cooperate and tell you about his involvement with the Omertas. He'll tell you he was smuggling guns in through the NCR supply shipments, and you can discuss destroying the guns. He'll give you some thermite and a key to destroy the guns the Omertas have been gathering for their secret plans, or if your speech is high enough you can convince him to plant the thermite himself. The guns are behind a unique door in the hotel, look for two flamers and two carbines (These will help later in the nest part of the quest). Place the thermite on the guns and set off the detonator near the door. If Troike plants the thermite himself he will get caught and rat you out before the Omertas kill him, but this wont ruin any of your objectives.

After you speak to Cachino about completing both objectives, he'll tell you the bosses need to be killed now. Luckily, they just put him in charge of finding out who's responsible for ruining their plans, and he'll lead you to a small room where the two bosses are. It is possible to convince Cachino to wait for your signal and he'll start shooting first with a speech of 80. If you didn't get the guns from the room when you used the thermite you can use the sawn-off shotgun Cachino gives you (or any holdout weapons you smuggled in) to kill the bosses. They'll ask you to have a seat, and the conversation will begin. They talk about how they know you've been ruining their plans and they want to kill you. At any point in the conversation you can start combat through a dialogue option, but it is possible with a speech of 80 to have Big Sal explain the whole plan to you, and you can convince Big Sal that Nero was helping you, and he'll start shooting nero when combat starts.

Once the bosses are dead the quest is complete and Cachino will take over the casino, if you speak to him after the fight he'll offer you 50 gamorrah tokens as thanks.