Microeconomic data specific to industries, suppliers, or products can often be found in commodity markets, trade exchanges, and financial databases. These provide detailed insights on supply, demand, pricing, and trends.
Reference: L4M5 Commercial Negotiation 2nd edition (CORE), Section 2.2 - Information Sources for Market and Economic Analysis

Reflecting on performance should become a natural final step in the negotiation process.
'Celebrating publicly about the deal': Public gloating, even in success or failure, if it gets back to the supplier via the press or social media, will likely damage the relationship
'Tempting TOP to reopen the negotiation': whether TOP agrees to reopen the negotiation, procurement should reflect on their achievement and what can be improved.
'Asking TOP for another concession': TOP can agree or reject this concession. Eventually, reflecting should be the final step. Procurement can learn a lot from reflection on performance.
LO 3, AC 3.4

According to Thomas-Kilmann conflict model instrument, there are 5 conflict management styles:
Accommodating is an unassertive and cooperative approach to resolving the conflict. Accommodating means conceding to the other party with little debate or fight, not challenging or strongly putting forward your own point of view and generally giving and yielding to the other party's point of view. Accommodating is best used when:
1. When others can resolve the conflict more effectively
2. When the issue is much more important to the other person than to yourself - to satisfy the needs of others and to show you are reasonable
3. To build up social credit for later issues which are important to you
4. When continued competition would only damage your cause
5. When preserving harmony and avoiding disruption are especially important
6. To aid in the managerial development of subordinates by allowing them to experiment and learn from their own mistakes LO 1, AC 1.1

Reference: CIPS L4M5 Study Guide, Section 3.1 - Planning and Preparation for Negotiation

Hammad's approach of presenting facts, figures, and justifications aligns with the Push persuasion method.
The Push strategy involves directly presenting information, data, and logical arguments to convince the other party of a certain outcome. In this scenario, Hammad is using objective evidence to influence the supplier towards agreeing to a discount, which is characteristic of the Push method, as per CIPS guidance on negotiation tactics.