Why did Vito negotiate with Don Fanucci?

Question

Vito starts the assassination by meeting with Don Fannucci, negotiating with him to lower the cost of protection, and succeeding. Shortly afterwards, Vito kills the Don and takes the money back.

My question is, why did Vito bother showing up with less money than was asked of him if he was going to kill and rob Fannucci anyway? From the conversation prior, it sounded like Vito and company had enough money to meet the original demands. Vito would have still met with Fannucci to pay him so the assassination route or plans wouldn't have changed. By negotiating, Vito risks potentially failing, angering Fannucci, and possibly getting roughed up or disabled before he can retrieve his gun (if not killed outright, it's unclear how much muscle or authority Fannucci actually had when Vito killed him.)

Why did Vito bother negotiating?

Answer 1

Why did Vito bother negotiating?

It's not precisely negotiating....just another tactic.

Certainly, he gives Fanucci less than was demanded but at the same time he indicates that he will come up with the balance.

          FANUCCI
        (Sicilian)
    I think there's only two hundred
    dollars under my hat.
        (he peeks)
    I'm right.  Only two hundred dollars.

          VITO
        (Sicilian)
    I'm a little short.  I've been out
    of work.  Let me owe you the money
    for a few weeks

Fanucci doesn't take offence, indeed, he seems quite impressed with Vito. This sort of "negotiating" would be expected...it demonstrates that Vito has character and strength.

This was a permissible gambit. Fanucci had the bulk of the money and would wait. He might even be persuaded to take nothing more or to wait a little longer. He chuckled over his wine and said, “Ah, you’re a sharp young fellow. How is it I’ve never noticed you before? You’re too quiet a chap for your own interest. I could find some work for you to do that would be very profitable.”

^{The Godfather - Mario Puzo}

In fact, the novel makes it clear that athougth Vito had already determined to kill Fanucci, he hesistates before taking the final step and takes more than enough money to pay Fanucci what he asks.

And yet he hesitated before taking the first step toward his destiny. He even packed the seven hundred dollars in a single fold of bills and put the money in a convenient side pocket of his trousers. But he put the money in the left side of his trousers. In the right-hand pocket he put the gun Clemenza had given him to use in the hijacking of the silk truck.

^{The Godfather - Mario Puzo}

Answer 2

My impression is that it was a final test of weakness. Fannucci even indicates in the car that he would be satisfied with less, which in itself is a sign of weakness, and when he finally does accept less with no pushback, in fact even the opposite in offering the guy who questioned his authority a job, I interpret that as the final confirmation that this man is not what he makes himself out to be, and that killing him would not be as risky as others may assume.

Answer 3

Vito tells his friends to tell Fannucci that they'll pay him whatever he wants after Vito asks them for £50 each.

So the question is whether or not Fannucci knew Vito was going to pay for himself and also for his friends.

1. If Fannucci did know this, then he gives Vito respect because, in his eyes, Vito stole from his friends to pay his debt leaving the debt of his friends pending. Fannucci respects this saying 'you got balls' because Vito appears to be playing about with his accomplices Tessio and Clemenza (pullings the strings) since they spoke a contradiction (they'd pay anything) to Fannucci before. But it's all planned by Vito and in reality, he is pulling the strings above Fannucci. Think about the consequences for everyone if what Fannucci realized was actual reality. Vito takes advantage of the situation by granting it as a favor to Tessio and Clem. It's beautiful.

2. If Fannucci didn't know this, then Vito pays half his expected debt to Fannucci (100 dollars) and Tessio and Clemenza told Fannucci they would pay him whatever he wanted. Tessio and Clemenza say these words but Vito is the only one to make the action (of paying). Playing with Fannucci's mind that Vito is better than his 2 accomplices, therefore, Fannucci would be more likely to go easy on Vito when Vito explains his situation of paying less. Vito keeps all of his money. This is a different type of manipulation to the previous possibility

But I think (1) is the true mentality of the writers because that sort of manipulation is what Michael Corleone does every time.