Negotiation variables such as price or contract length, etc are that can be traded with TOP in a negotiation.
The more variables you can identify, the better. The more variables you can identify and articulate, the lower the chances of the negotiation reaching deadlock as more possibilities are facilitated regarding more creative solutions.
Below are examples of negotiation tradeables in buying professional services:
LO 2, AC 2.3

An organisation's expense can be categorised into three groups:
Fixed Costs - costs that do not change with output.
Variable Costs - costs that vary in direct proportion to output.
Semi-variable costs - costs that are a combination of the above, with both a fixed and variable element.
Among the four options:
"Land rental paid in advance": This is fixed cost. The rental won't increase when the production increases.
"Additional pallet hires due to higher demand in year-end season": This can be identified as semi-variable cost (or step cost).
"Governments taxes": The taxes are often levied by a percentage of income or revenue. Therefore, it is variable
"Raw materials for next year production": This is obviously variable cost.
Reference:
CIPS study guide page 79-84
Study tips: Fixed variable and semi-variable costs - AAT Comment

There are multiple sources of divergent positions that can arise in situations where money is exchange for goods and services. There are 2 different types of sources. Those that arise from the content or subject matter of the negotiation (what is being negotiated) and those that arise from the process of negotiation (how it is being negotiated).
Sources of divergent position - the content of negotiation:
Table Description automatically generated

Cultural differences are the source of conflict in the process of negotiation.
Requisition is an internal document raised by user or store to communicate to procurement the need to buy the product or service specified. This is merely a internal document.
Framework arrangement is a rather loose set-up, without any legal standing. It usually occurs when an organisation has decided for itself to limit the number of suppliers it is willing to work with and, through a purely internal process, sets up an approved list of such suppliers.
LO 1, AC 1.1

Connected stakeholders are those who, by contractual or commercial relationships, have a significant stake in organisation activity. As a general rule, connectedstakeholder (with the exception of suppliers) have a low level of influence on procurement negotiations.
Examples of connected stakeholders are: suppliers, customers, bank where the organisation opens its account, shareholders.

Integrative negotiationfocuses onmutual gainand long-term collaboration. It seeks tomaximize joint outcomesand encourages parties to align interests andpursue shared goals. This contrasts with distributive tactics that prioritize individual wins and short-term gains.
"Integrative negotiations aim to create outcomes where both parties benefit. Shared problem-solving, information exchange, and joint goal pursuit are central features of this approach." (L4M5 Commercial Negotiation, 2nd edition, Section 1.1 - Principles of Integrative Negotiation)